RU2494151C2 - Top coating - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: coating film contains: a layer of coloured coating formed from a mixture of a hard component (10% modulus is greater than 2.3 but not grater than 3.0) and a soft component (10% modulus is greater than 0.0 but not greater than 1.0) of a two-component polyurethane resin; and a top coating layer formed from a mixture of a middle component (resin with 10% modulus greater than 1.0 but not greater than 2.3) and a soft component (resin with 10% modulus greater than 0.0 but not greater than 1.0) of a two-component polyurethane resin. The coating film formed from a top coating layer maintains properties of the material, such as strength and wear resistance.

EFFECT: when a consumer touches natural leather, the coating layer on the surface of the natural leather provides pleasant characteristics of natural leather and smoothness.

5 cl, 11 dwg, 4 tbl, 18 ex

Description

FIELD OF THE INVENTION

The present invention relates to genuine leather, which is a natural tanned skin with a cover film formed thereon.

State of the art

Genuine leather is a popular option as a material for parts of an automotive interior. Such popularity is due to the excellent characteristics of genuine leather. At the same time, since customers require high-quality features for cars, natural leathers also add new properties suitable for such high-quality features. More specifically, for car seats that are used in car interiors, genuine leathers are required to provide a comfortable tactile feel, strength and durability. Recently, natural leathers are in demand, which, when in contact with a person sitting on a seat, feel soft to the touch, while at the same time retaining sufficient strength.

At present, one of the characteristics of genuine leather that is in demand in this industry, where the characteristic features of an even higher quality are required, is still not provided to the necessary extent with ordinary genuine leathers, that is, a unique tactile sensation is not provided, although strength is still in demand. wear resistance and other characteristics of ordinary genuine leathers. In other words, new genuine leather is required to provide a unique tactile feel.

The meaning of the term “unique tactile sensation” can be expressed on the basis of technical characteristics. More specifically, such a new genuine leather should contain a coating film layer formed on it, the characteristics of which are such that the strength, wear resistance and other physical properties of the coating film are the same as the properties of existing natural leathers, but when a person is in direct contact with such genuine leather, he feels the distinctive characteristics of the skin, such as evenness and smoothness, inherent only in natural skin.

Currently, a coating film layer providing such characteristics is required. However, as far as the authors of the present invention are aware, such genuine leather is not currently on sale.

The following discusses what kind of technical inventions have been proposed in order to provide a coating film layer with the characteristics of ordinary natural leathers.

The traditional requirements for car seats made of genuine leather include the tactile feel of genuine leather, strength and durability. Such requirements are met by the formation of a coating film layer using synthetic resin. In order to form a patterned pattern (measure) characteristic of the skin on the surface, aniline finish of the skin was applied to form a coating film, which was associated with high transparency of the finishing coating film. Modified aniline finishes include an aniline-like finishes, a semi-aniline finishes, and a coat. Instead of such treatments, the current trend offers the formation of a coating film using a polymer, a polymer emulsion or a water-based polymer emulsion, and polyurethane is a popular choice as a polymer. In other words, currently layers of the coating film are formed using polymers, polymer emulsions and water-based polymer emulsions.

Polyurethane resins used to form the coating film include resins containing a moisture curable one component varnish; resins in need of an additive to be added to the water-based dispersant for a polymer with blocked isocyanate groups; and resins that require the use of a skin tanning agent aimed at creating polyurethane with terminal aromatic amino acid groups by reaction with a chain terminating agent. It is believed that a two-component polyurethane resin based on a mixture of polyol and isocyanate components may be suitable as a coating film, and in recent years, water-based two-component polyurethane resins have been introduced due to environmental problems associated with solvents.

In order for the coating film to fully demonstrate its structural properties, studies were conducted aimed at developing a coating film layer containing a two-component polyurethane resin and various additives.

In the formation of the coating film, a three-stage method is applied in which a lower coating layer (primer), a middle coating layer and a top coating layer are applied, and in particular, various technically necessary materials are added to the upper coating layer formed on the upper coating (Patent Literature 1 : Japan Patent No. 3725569, Japanese Patent Laid-open No. Hei 08-67900 / Patent Literature 2: Japanese Patent Laid-Open No. 2005-330358 / Patent Literature 3: Japanese Patent Laid-open No. 2004-18779).

Polymeric materials have a unique relationship between stress and tensile strain (S-S curve) (Figure 1: drawing explaining stress-strain curves for conventional resins). When an external force is applied to the polymer material, a voltage corresponding to the external stress is generated inside the material, and at the same time, the material is stretched. The above curve shows such a state. This stress gradually increases until it finally reaches the yield strength (1A) (σY indicates the stress at the yield strength, while εY represents the strain at the yield strength). As soon as the indicated point is passed, the proportional relationship between stress and strain disappears, and irreversible deformation remains even after the stress is removed. If stress is applied continuously, ultimate strength (1B) is reached (σB indicates stress at ultimate strength, while εb is deformation at ultimate strength) and the polymer material will burst (Non-Patent Literature 1: General SS Curve (section "Shape of Stress vs. Strain Curve ") on page 102 of" Plastic Data Book, "published by Asahi Kasei Amidas Corporation et al. And published by Kogyo Chosakai Publishing, Inc., December 1, 1999). On the other hand, polymeric materials can be classified according to the type according to the shape of their tensile stress – strain curve, as shown in the figure explaining the types of resins based on the stress-strain curve of the resins (FIG. 2) (non-patent literature 1: p. 102 (section "Classification of Plastics by Type of SS Curve"), "Plastic Data Book", published by Asahi Kasei Amidas Corporation et al. And published by Kogyo Chosakai Publishing, Inc., December 1, 1999. ) In Fig. 2, stress-strain curves are divided into curves for a 2A-type polymer (soft and weak (elastic modulus: small; tensile strength: low; elongation: medium)), for a 2B-type polymer (hard and brittle ( elastic modulus: small; tensile strength: medium to high; tensile strength: small)), for 2C-type polymer (hard and strong (elastic modulus: large; tensile strength: high; tensile strength: medium)), for 2D polymer -type (hard and non-brittle (elastic modulus: small; tensile strength nii: medium; elongation: large; or elastic modulus: medium; tensile strength: medium to high; elongation: large)), or for a 2E-type polymer (rigid and non-brittle (elastic modulus: large; tensile strength: high , elongation: large)). Such dependencies are used to select polymeric materials with the required characteristics. You can also focus on specific materials (such as polyurethane materials) and research on how the characteristics of specific materials change when their stress-strain curve changes when their components change, in order to select a material that provides the required characteristics.

A specific example of solving the problems that are often encountered when choosing a stress-strain curve, which is closely related to good wear resistance and softness characteristics, is described below.

The present invention was developed with the aim of creating a leather material that provides durability and maintains softness, while also providing an improved tactile feel, where the present invention is characterized as follows: "Leather material consisting of genuine leather or artificial leather, formed on it a layer of polymeric material in which the aforementioned layer of polymeric material contains a silicone copolymer, and in which a stress of not more than 2.4 MPa is created at 20% deformation, or a stress of 3.5 MPa or more at 100% strain "(Patent Literature 4: Japanese Patent Laid-Open No. 2007-277323). The description of the aforementioned invention includes such a statement regarding a silicone copolymer: "if the stress at 20% deformation exceeds 2.4 MPa, the tactile sensation worsens, and if the stress at 100% deformation is less than 3.5 MPa, wear resistance decreases "(0015). In order to obtain softness and wear characteristics, this problem was solved by determining a suitable silicone copolymer.

Another example is described below related to an attempt to select a specific polymer and then add specific components to the polymer in order to achieve the desired effects. An invention has been published which is a "dressing for skin surface finishing, consisting of a water-based resin composition that contains 100 parts by weight of a two-component polyurethane resin (A), from 40 to 100 parts by weight of a polyisocyanate crosslinking agent (B), from 5 to 25 parts by weight of silicone compound (C) and from 5 to 120 parts by weight of filler (D), in which the aforementioned silicone compound (C) is a polyether modified silicone "(Patent Literature 5: Patent Laid-Open I Pony No. 2007-314919).

The aforementioned invention relates to a skin surface finishing coat consisting of a water-based resin composition, which essentially does not contain an organic solvent, has excellent stainability and is capable of adding high wear resistance to the skin; as well as skin made using such a surface finishes, in which a water-based polyurethane resin is mixed with an excess of a polyisocyanate crosslinking agent and a silicone compound to which an organic or inorganic filler is added in order to provide excellent stainability and add high wear resistance to the skin, in fact, without the use of an organic solvent.

The following is an example of the determination of a urethane polymer with the addition of silicone and fine powder as binders.

In order to achieve a pleasant tactile sensation, the coating material used to form the coating film layer must provide wear resistance and also remain soft, and the present invention relates to a topcoat layer designed to simultaneously provide wear resistance and a pleasant tactile sensation in which such a topcoat layer characterized by its stiffness usually from 2.0 to 5.0 microns in a standard state; a binder, such as urethane or silicone, is mixed with a solvent, such as toluene or MEK, as well as fine powder, etc., and the resulting mixture is applied to the base material, while providing a layer of a top coating containing fine powder, and roughness surface Ra which in the standard state is in the specified range (patent literature 6: Japanese Patent Laid-Open No. 2006-307397).

As can be seen from the above, the problem of providing this characteristic required from ordinary genuine leathers could be solved by choosing one type of polymer material suitable for the characteristic, and then determining additional components required for such a material.

As for the layer of the coating film, which represents the sphere of interests of the authors of the present invention, the search begins with the definition of what constitutes a “unique tactile sensation”. In particular, the “unique tactile sensation” refers to the characteristic of evenness specific to genuine leather, as well as to the smoothness (distinctive characteristics of the skin) provided by a layer of a coating film present on the surface of genuine leather, and felt when the consumer touches the natural skin directly, at the same time, such a layer of the coating film retains the strength, wear resistance and other physical properties of conventional coating films. The task of obtaining such a new coating film has already been mentioned above.

Although the distinctive characteristics of the skin include evenness and smoothness, they are two different characteristics, and depend on the stress-strain curves of the common individual components; obtaining such two different characteristics at the same time is of course difficult.

In order to provide two new heterogeneous characteristics, attempts have been made to mix polymeric materials with different characteristics, such as components of the combinations described below, to provide new, required characteristics.

In order to provide a film with hitherto unattained levels of hardness, elasticity and resistance to solvents, an invention was made that uses a two-component polyurethane dispersant made from a composition that contains a first component based on water dispersible polyurethane, a second component based on water dispersible polyisocyanate and polyol of the first and second components, (Patent Literature 7: Japan Patent No. 2,707,169, Japanese Patent Laid-open No. Hei 4-233983).

There is another invention in which a polyurethane composition is provided by mixing a thermoplastic low hardness polyurethane with a high hardness thermoplastic polyurethane, where the obtained polyurethane composition provides excellent resilience, elasticity, dynamic strength, etc. (Patent Literature 8: Japanese Patent No. 3419593, Japanese Patent Laid-open No. Hei 9-3321). Likewise, the invention relates to a composition comprising a conjugated diene block copolymer of a vinyl aromatic compound (Patent Literature 9: Japanese Patent Laid-open No. Hei 9-25407). In addition, there is an invention related to a thermoplastic resin composition consisting of a defined thermoplastic polyurethane with a hardness of 55 to 85 according to the Japanese JIS A standard and an olefin elastomer with a hardness of 40 to 80 according to the Japanese JIS A standard in which such a composition has excellent characteristics of thermoplastic polyurethane or, in particular, excellent film stability, ease of removal from the mold and resistance to adhesion, while maintaining other dynamic characteristics, such as resilience elasticity, high levels of extensibility and elasticity, and which can be used for manufacturing films, sheets, etc. (Patent Literature 10: Japanese Patent No. 3630820, Japanese Patent Laid-open No. Hei 9-208820). Another related invention is an invention in which a foam layer of a high-density fiber-reinforced urethane resin and a foam layer of a low-density urethane resin are molded in one process, despite high relative expansion (contrast), to achieve molding that provides a good balance of heat resistance, strength at bending and stiffness (Patent Literature 11: Japanese Patent Laid-Open No. Hei 11-58534 / Patent Literature 12: Japanese Patent Laid-Open No. Hei 10-296939). Other inventions include a product containing a two-component, water-based polyurethane film providing improved impact resistance, high stability, and excellent optical performance (Patent Literature 13: Published Japanese translation of PCT International Patent Application No. 2002-533488); a product consisting of a base and a layer of a coating film formed on top, in which such a coating film layer contains a chromogenic composite fiber that reflects visible light and exhibits color, and which are formed by alternately applying two types of polymeric materials with different refractive indices of light (patent literature 14: Japanese Patent Laid-Open No. 2002-67239); and a flat panel combined with two or more types of polyurethane layers 2, 3 having different characteristics and formed on the same plane to provide a thin but solid polyurethane foam providing high strength, high rigidity and high heat resistance (Patent Literature 15 : Japanese Patent Laid-Open No. 2007-321031). In addition, by crosslinking a lactone-modified polyol with at least two types of polyisocyanates, including isophorondiisocyanate, an urethane resin was created in which, despite the unique tendency of such a material of low hardness urethane resin to give significant residual compression, both hardness and and residual compression are balanced at sufficiently low levels, and as a result, residual compression can be reduced (Patent Literature 16: Japanese Patent Laid-Open No. 2007-298662). Another invention relates to a polishing pad of a layered structure for semiconductor wafers consisting of a polyurethane foam layer, a resin layer with a higher elastic modulus than the polyurethane foam layer (second layer), and a layer with a lower elastic modulus than the aforementioned second layer located on the opposite side of the second layer of polyurethane foam (third layer) (Patent Literature 17: Japan Patent No. 3788729, Japanese Patent Laid-Open No. 2002-75933).

These specific examples do not suggest that it is possible to ensure evenness and smoothness, which are characteristic inherent only in natural skin, for example, by mixing two different types of polymeric materials, such as polyurethane resins.

Before working on the present invention, the inventors examined the tanning stage and the retanning stage in the production of genuine leather, and obtained genuine leather with “firmness, softness, characterized by more significant elasticity than is usually expected from the skin, no more stretch than usual the level of skin extensibility, as well as the ability to restore "(Japanese patent application No. 2007-170359).

It is expected that as a result of the present invention it will be possible to obtain natural skin that has a softness characterized by greater elasticity than is normally expected from the skin, not more extensibility than the usual level of skin extensibility, as well as the ability to restore, in which the layer of the coating film present on the surface of such genuine leather, retains strength, wear resistance and

other physical properties of ordinary coating films and has the evenness and smoothness inherent only in natural skin when the consumer directly touches natural skin.

Patent Literature 1: Japanese Patent No. 3725569, Japanese Patent Laid-Open No. Hei 08-67900

Patent Literature 2: Japanese Patent Laid-Open No. 2005-330358

Patent Literature 3: Japanese Patent Laid-Open No. 2004-18779

Patent Literature 4: Japanese Patent Laid-Open No. 2007-277323

Patent Literature 5: Japanese Patent Laid-Open No. 2007-314919

Patent Literature 6: Japanese Patent Laid-Open No. 2006-307397

Patent Literature 7: Japanese Patent No. 2,707,169, Japanese Patent Laid-Open No. Hei 4-233983

Patent Literature 8: Japanese Patent No. 3419593, Japanese Patent Laid-Open No. Hei 9-3321

Patent Literature 9: Japanese Patent Laid-Open No. Hei 9-25407

Patent Literature 10: Japanese Patent No. 3630820, Japanese Patent Laid-Open No. Hei 9-208820

Patent Literature 11: Japanese Patent Laid-Open No. Hei 11-58534

Patent Literature 12: Japanese Patent Laid-Open No. Hei 10-296939

Patent Literature 13: Published Japanese Translation of PCT International Patent Application No. 2002-533488

Patent Literature 14: Japanese Patent Laid-Open No. 2002-67239

Patent Literature 15: Japanese Patent Laid-Open No. 2007-321031

Patent Literature 16: Japanese Patent Laid-Open No. 2007-298662

Patent Literature 17: Japanese Patent No. 3788729, Japanese Patent Laid-Open No. Hei 2000-75933

Non-Patent Literature 1: Classification of Plastics by Type of S-S Curve section on page 102 of the Plastic Data Book published by Asahi Kasei Amidas Corporation et al and published by Kogyo Chosakai Publishing, Inc. December 1, 1999

SUMMARY OF THE INVENTION

Problems to be Solved by the Invention

An object of the present invention is to provide genuine leather with a layer of a new coating film in which such a coating film layer present on the surface of natural leather preserves the physical properties of the coating films, such as strength and wear resistance, and at the same time, when the consumer directly touches the natural skin, also demonstrates the distinctive characteristics of the skin, such as evenness and smoothness, inherent only in natural skin.

Another objective of the present invention is to obtain genuine leather with a layer of a new coating film, in which such a layer of a coating film present on the surface of natural leather preserves the physical properties of the coating films, such as strength and wear resistance, and at the same time, when the consumer directly touches to natural skin, also demonstrates the distinctive characteristics of the skin, such as the evenness and smoothness inherent only to natural skin, and also in which genuine leather, representing oboj basis for the layer coating film does not stretch more than the usually expected from natural leather and also has the ability to recover.

Means for solving the problem

(1) (A) The authors of the present invention tried to provide a coating film layer that retains the physical properties of conventional coating films, such as strength and wear resistance, while also demonstrating evenness and smoothness inherent only to natural skin when the consumer directly touches the natural skin skin.

(B) For an objective assessment and decision regarding the results obtained when developing genuine leather with the above characteristics, it was necessary to perform measurements using measuring instruments capable of expressing the required characteristics as accurately as possible, with subsequent determination based on the measurement results, has or not, a layer of a coating film, both evenness and smoothness, inherent only to natural skin.

(C) The following paragraphs relate to the quantitative measurement of the properties of a newly formed coating film (according to the measurement methods illustrated in FIG. 13, which is a FIG. Explaining the measurement of evenness using KES, and in FIG. 14, which is a FIG. illustrating the measurement of smoothness using KES), and if the obtained values reach the intended values determined in advance, the coating film is considered suitable (positive).

(a) Measurement of evenness (FIG. 13)

Evenness is measured as surface friction.

(i) Measurement of average surface friction coefficient (MIU)

The friction force sensor 13A (shown in FIG. 13a) is attached to the holder of the friction force sensor 13G in the friction force measurement system 13D (13b) to measure surface friction μo and calculate the average surface friction coefficient μm (MIU) (13c). The average surface friction coefficient μm (MIU) is an indicator of surface slippage.

(ii) Measurement of the average deviation of the coefficient of surface friction (MMD)

Similarly, calculate the average deviation (also called the "spread of the coefficient of surface friction" or MMD) from surface friction μo. The average deviation of MMD is an indicator of surface roughness (13c).

(iii) A method for calculating evenness inherent only in natural skin.

Evenness can be calculated by calculating the aforementioned average surface friction coefficient (MIU) (i) and the average deviation of the surface friction coefficient (MMD) (ii) (average surface friction coefficient (MIU) / average deviation of the coefficient of surface friction (MMD)).

(iv) When the ratio “average surface friction coefficient (MIU) / average deviation of the coefficient of surface friction (MMD)” is used as an evenness indicator, this means that a larger calculated value corresponds to a better tactile surface feel. For practical applications, the calculated value should be 25 or more.

(b) Whether the coating film is smooth or not is determined by measuring the surface roughness and obtaining its average deviation (Fig. 14). Fig. 14a consists of Fig. 14a (illustrating the device of the surface roughness sensor), Fig. 14b (a system for measuring friction using a surface roughness sensor) and Fig. 14c (illustration of the average deviation of the SMD based on the measurement of surface roughness using a surface roughness sensor) surface).

(i) Calculation of SMD (average surface roughness deviation)

Regarding surface roughness, a surface roughness sensor (14A, also referred to as a “U-shaped sensor”) moves along a coated surface formed on the skin surface, and a vertical thickness change is measured with a surface roughness sensor in order to measure surface roughness and calculate the average surface roughness deviation (SMD). The average surface roughness deviation (SMD) is an indicator of surface smoothness.

(ii) SMD (Mean Surface Roughness Deviation) is considered acceptable if its value is 2.5 μm or less.

(D) Whether or not the physical properties of the coating film, such as wear resistance, are retained, is checked by measuring the following evaluation points:

(a) Wear resistance

(i) The wear resistance tester (Fig. 15) should correspond to the figure showing the friction roller (60 mm wide, 25 mm thick) (15a), as well as the device for determining the assessment of material resistance to abrasion according to Gakushin (Gakushin, 15B) on which such a friction roller is mounted (Fig. 15b shows a general view of the testing apparatus, model AB301 manufactured by Tester Sangyo). The test piece (15C) is mounted on the friction roller (15A) of the wear test device, as shown in 15a, the friction roller is connected to the load (15F) and the piece of cotton canvas No. 6 (15D) is fixed on the device to determine the assessment of the material's abrasion resistance according to Gakushin (Gakushin, 15B). Friction is used until the coating film exfoliates, while at the same time, the state of the coating film is observed with the naked eye. To obtain a Gakushin wear resistance rating, the number of forward and backward movements of the roller is recorded, after which the cover film begins to peel off, and the average of the counts made for the two pieces tested is calculated.

(ii) The coating film was believed to have the required properties, such as strength and wear resistance, when the result of the aforementioned wear test (measurement using a Gakushin abrasion resistance assessment tool) was 4,000 cycles or more.

(E) The strength of the formed coating film layer is measured by measuring the strain of the resin forming the coating film layer with respect to the stress applied to the resin (that is, by obtaining a stress-strain curve). The measurement method should correspond to the method in which the dumbbell-shaped sample is used.

(a) Preparation of the test piece (Fig. 16)

Pour the resin into a silicone mold and leave it for at least 3 days at room temperature (20 ± 5 ° C) until dry to prepare a resin-based film with a thickness of about 0.4 to 0.8 mm.

To die test piece of dumbbell shape (Fig. 16) from a resin film, a stamping template is used. In the center of the test piece, marks are made at a distance of 30 mm.

Width of test piece W (mm) = 20

The initial distance between the marks on the test piece Lo (mm) = 30

(b) Test method

To obtain the thickness of the test piece T (mm), the thickness of the test piece is measured at 3 points C, L and R, as shown in FIG. 16, and the average value is obtained from the values measured at three points.

Obtaining a load-tensile curve

To obtain a curve illustrating the relationship between the applied load and the stretch between the marks, a Tensilon tensile tester (AG-1 AUTO GRAPH manufactured by Shimadzu) is used, pulling the test piece at a speed of 100 ± 20 mm / min until it breaks.

Obtaining a stress-strain curve

To obtain an equivalent voltage, divide the load by the cross-sectional area according to the formula below:

S = P / (W × T)

S: stress (MPa)

P: load (N)

W: width of test piece (mm)

T: test piece thickness (mm)

To obtain equivalent deformation (elongation), use the following formula for the amount of stretching between the marks:

s = ΔL / L _o × 100

s: strain (%)

ΔL: stretch between marks (mm)

L _o : initial mark spacing (mm)

10% module

The stress corresponding to 10% strain is defined as 10% modulus (unit: MPa).

(2) Based on their past practical experience, the authors of the present invention believe that when forming a coating film with a polyurethane resin, the application of the following formation method could lead to a coating film providing the above characteristics, and accordingly decided on the formation of the coating films.

A particular method relates to the formation of a coating film on the surface of genuine leather (base) obtained by the tanning step and the stages of retanning, dyeing and fatliquoring (natural leather before the formation of the coating film is hereinafter referred to as the "base", while genuine leather after that as a cover film is formed, is referred to as “genuine leather” to distinguish between the two). First, a primer layer is formed, followed by the formation of a base coat layer. The primary role of the primer layer is to prevent the penetration of the basecoat material into the substrate, which is especially important when a semi-aniline finish is applied while maintaining a small thickness of the basecoat. The primer layer also enhances the adhesion between the substrate and the base coat, and is especially important when the face layer on the surface of the substrate is not scraped off but retained. The primer material almost completely penetrates the base. The main coating layer is used to smooth out other irregularities on the surface of natural leather to create a stable surface for the coating film, and it becomes the basis for the layer of coating film formed on it. The base coat layer also plays a role in providing better adhesion to the painted coating layer formed on it, while it holds the painted coating layer and prevents it from peeling off. Such layers play an important role in the formation of a layered structure. The inventors, thanks to their practical experience, knew that such layers did not directly affect the tactile sensation of the coating film, and that, first of all, the coating film formed on such layers could be directly related to the tactile sensation. Accordingly, the authors of the present invention believe that the key to solving the problem lies in the coincidence of the properties of the layer formed on top of such layers with the previously mentioned required properties.

(3) Traditionally, a skin cover film for a car seat, etc. form in three layers, where only the top layer as a coating film has sufficient strength characteristics, and form from a two-component polyurethane resin, providing wear resistance and strength. The inventors believe that, given the characteristics obtained due to such a two-component polyurethane resin, and based on its stress-strain curve, a film could be formed to provide the intended characteristics of the polyurethane when a coating film was formed.

(4) In fact, it has been found that it is possible to efficiently mix several two-component polyurethane resins set according to a specific stress-strain curve and accordingly form a colored coating layer and a top coating layer, as explained below.

It should be noted that the 10% modulus mentioned below in the description refers to the level of tensile force (tension), resulting in 10% elongation (elongation). Actual combinations are listed below.

(A) Genuine leather is made by mixing a hard component (resin, whose 10% modulus is greater than 2.3, but not more than 3.0) of a resin containing a two-component polyurethane resin and polyurethane resin, with a soft component (resin, whose 10% modulus is greater 0.0, but not more than 1.0) a resin containing a two-component polyurethane resin and a polyurethane resin to form a colored coating layer, followed by the middle component (resin, whose 10% modulus is greater than 1.0, but not more than 2.3) resin containing a two-component polyurethane resin and polyurethane resin, see Shiva with a soft component (a resin whose 10% modulus greater than 0.0 but not more than 1.0) of the resin containing two-component polyurethane resin and polyurethane resin, to form a topcoat layer.

(B) When the ratios of the above-mentioned components in the mixture are discussed, the foregoing can be specified as follows.

Genuine leather is characterized in that the aforementioned colored coating layer is formed by mixing from 48 to 90 weight percent of the hard component (resin, whose 10% modulus is greater than 2.3, but not more than 3.0) of a resin containing a two-component polyurethane resin and polyurethane resin, and from 52 to 10 weight percent of the soft component (resin, whose 10% modulus is greater than 0.0, but not more than 1.0), a resin containing a two-component polyurethane resin and a polyurethane resin; while the aforementioned topcoat layer is formed by mixing from 15.0 to 35.0 weight percent of the middle component (resin, whose 10% modulus is greater than 1.0 but not more than 2.3) of a resin containing a two-component polyurethane resin and polyurethane resin, and from 65.0 to 85.0 weight percent of the soft component (resin, whose 10% modulus is greater than 0.0, but not more than 1.0), a resin containing a two-component polyurethane resin and a polyurethane resin.

(5) In developing the present invention, the inventors used as a base the genuine leather described in the present invention (Japanese Patent Application No. 2007-170359, which describes leather, in particular, many test examples included in this description).

Such test examples are collectively referred to as Example 1. Examples 2-10 are examples in which coating films are formed on the surface of a substrate (BLC50) obtained in Test 6 of Example 1.

Among them, Examples 2-6 are specific examples of mixing soft and hard components for a colored coating layer, and mixing medium and hard components for a topcoat layer to form a colored coating layer and a top coating layer in the form of a coating film formed on the surface of the substrate described in example 1. On the other hand, examples 7-10 describe examples of studies of what happens when the ratios in a mixture of soft and hard components forming a layer of a painted coating change , While the mixing ratio of medium and hard components constituting the top coat layer, remain the same.

Example 11 is a specific example showing that positive results were obtained when the base obtained in Example 1 (BLC50) was scrubbed by grinding and a coating film was formed on the obtained skin base.

Example 12 is a specific example showing that positive results were obtained when a coating film was formed on a chrome tanned leather surface.

On this basis, the aforementioned coating film was formed.

(6) The above estimates were performed for each base on which the coating film was formed.

(7) The evaluation results are shown in table 4.

(a) According to the measurements of natural leathers with a coating film formed on them using the KES-SE-SR-U friction roughness measurement device (manufactured by Kato Tech), the smoothness (SMD) was 1.8 μm or less, while while evenness (MIU / MMD) was 25 or more. Regarding smoothness (SMD), all measured values ranged from 0.70 μm to 1.50 μm, which leads to the conclusion that a criterion of 2.5 μm or less was satisfied.

Regarding evenness (MIU / MMD), all measured values were in the range of 26.3 and 34.3, indicating that the criterion for evenness (MIU / MMD) of 25 or more was met.

(b) Regarding the wear test using a Gakushin abrasion resistance assessment tool, all measured values ranged from 5,000 to 10,000 cycles, indicating that a criterion of 4,000 cycles or more was met.

(c) All of the substrates on which the aforementioned coating film was formed met the criteria specified in points (a) and (b) above and therefore constitute the skin type actually necessary for the present invention.

Effects of the invention

According to the present invention, it is possible to obtain natural skin with a layer of a new coating film in which such a coating film layer present on the surface of natural leather retains the physical properties of conventional coating films, such as strength and wear resistance, while also demonstrating evenness and smoothness inherent only for genuine leather, which are characteristics not provided by ordinary genuine leathers, when the consumer directly touches the natural skin by primer and then the main coating on the surface of genuine leather, obtained using the tanning stage and the stages of retanning, dyeing and fatliquoring, and the subsequent formation on the surface of natural leather of a painted coating and a layer of top coating, both of which consist of specific components.

By using genuine leather as a base as described in Japanese Patent Application No. 2007-170359, or by grinding the aforementioned genuine leather, followed by using scraped leather as a base, or by using chrome tanned leather as a base, and then forming on the surface any of these bases of the coating film described in the present invention, you can get a new natural skin, giving the desired tactile sensation, which is a characteristic not provided by conventional mi genuine leathers.

Genuine leather in accordance with the present invention is applicable as a material for parts of an automotive interior, such as steering wheels, seats, doors, dashboards, handrails and other handles.

Brief Description of the Drawings

Figure 1: a drawing explaining the stress-strain curves for conventional resins.

Figure 2: a drawing explaining the types of resin depending on the stress-strain curves of the resins.

Figure 3: a drawing showing the stress-strain curve of a two-component aliphatic polyurethane (whose 10% modulus is 2.88), used as a matting agent.

4: a drawing showing a stress-strain curve of a two-component aliphatic polyurethane (whose 10% modulus is 2.77).

5: a drawing showing a stress-strain curve of a two-component aliphatic polyurethane (whose 10% modulus is 0.54).

6: a drawing showing a stress-strain curve of a two-component aliphatic polyurethane (whose 10% modulus is 0.30).

FIG. 7: a drawing showing a stress-strain curve of a resin of a colored coating layer obtained by mixing resins whose stress-strain curves are shown above in FIGS. 3, 4, 5 and 6.

Fig. 8: a drawing showing a stress-strain curve of a two-component aliphatic polyurethane resin (whose 10% modulus is 1.89).

Fig. 9: a drawing showing a stress-strain curve of a two-component aliphatic polyurethane (matting resin) (whose 10% modulus is 0.67).

10: a drawing showing a stress-strain curve of a two-component aliphatic polyurethane resin (whose 10% modulus is 0.54).

11: a drawing showing a stress-strain curve of a copolymer of an acrylic polymer and a urethane polymer (whose 10% modulus is 0.11).

12: a drawing showing a stress-strain curve of a resin of a topcoat layer obtained by mixing resins whose stress-strain curves are shown above in FIGS. 8, 9, 10 and 11.

Fig. 13: a drawing explaining the measurement of evenness using KES.

FIG. 14: a drawing explaining smoothness measurement using KES. FIG.

Fig. 15: a drawing explaining a device of a device for determining an estimate of a material’s resistance to abrasion according to Gaushin.

Fig. 16: a drawing explaining a measurement of the stretch of a test piece.

Fig: drawing, specifying the percentage of the retanning device.

Fig: drawing, specifying the maximum percentage of Al.

Character Description

1A — yield strength;

1B - ultimate strength;

σy is the yield stress;

εy — deformation at yield strength;

σB is the stress at ultimate strength;

εb — strain at ultimate strength;

2A — stress-strain curve of soft and weak type (elastic modulus: small, tensile strength: low, tensile strength: medium);

2B is a stress-strain curve of a hard and brittle type (elastic modulus: small; tensile strength: medium to high, tensile: small);

2C - stress-strain curve of hard and strong type (elastic modulus: large, tensile strength: high, elongation: medium);

2D - stress-strain curve of hard and non-brittle type (elastic modulus: small, tensile strength: medium, tensile strength: large; or elastic modulus: medium, tensile strength: medium to high, tensile strength: large);

2E - stress-strain curve of hard and non-brittle type (elastic modulus: large, tensile strength: high, tensile strength: large);

13a is an enlarged view showing a friction force sensor device;

13b is a drawing showing a system for measuring friction using a friction force sensor;

13c is an illustration of the average deviation of the MMD obtained from a measurement of surface friction (μo), and also an illustration of the average coefficient of surface friction (MIU, μm)

13A is a friction force sensor;

13B — completion of friction force detection (manual adjustment);

13C — friction force detection unit;

13D is a system for measuring friction;

13E is a sample;

13F - direction of movement;

13G - holder of the friction force sensor;

14a is an enlarged view showing a surface roughness sensor device;

14b is a drawing showing a system for measuring friction using a surface roughness sensor;

14c is an illustration of the average deviation of the SMD obtained from measuring a surface roughness using a surface roughness sensor;

14A is a surface roughness sensor;

14B - completion of the detection of surface roughness (manual adjustment);

14C is a surface roughness detection unit;

14D is a system for measuring surface roughness;

14E is a sample;

14F - direction of movement;

14G - holder of the surface roughness sensor;

15a is a drawing showing a friction sensor (roller);

15b is a device for determining the assessment of the resistance of a material to abrasion according to Gakushin, equipped with a friction sensor (roller);

15A - friction sensor (roller);

15B is a device for determining an assessment of a material’s resistance to abrasion according to Gakushin;

15C — test piece;

15D - cotton canvas;

15E - lever under load;

15F - load.

BEST MODE FOR CARRYING OUT THE INVENTION

The present invention relates to a coating film based on genuine leather, which is produced using a traditionally known technological process, which includes the stage of tanning of the skin with subsequent stages of neutralization, retanning, dyeing and fatliquoring. Such genuine leather may be genuine leather, the condition of which, in particular, limits the provision of the desired characteristics, or genuine leather produced by a conventional production method.

When a layer of a coating film according to the present invention is formed on the basis of genuine leather produced by a conventional method, it is possible to obtain natural skin with a layer of a coating film that retains the physical properties of conventional coating films, such as strength and wear resistance, and at the same time, when the consumer directly touches natural skin, it also demonstrates the evenness and smoothness inherent only to natural skin, which are characteristics not provided by ordinary skin linen skins.

The present invention provides hitherto inaccessible genuine leather with elasticity, softness, characterized by greater elasticity than is usually expected from the skin, not more extensibility than the usual level of skin extensibility, as well as the ability to restore where such natural skin can be obtained without the use of chromium as a tanning agent (Japanese Patent Application No. 2007-170395). The characteristics of such skin are quantitatively expressed as follows: "stiffness / softness of 5.0 mm or more, and a maximum percentage of permanent deformation of 10% or less"; and "stiffness / softness of 4.42 mm or more, but not more than 4.90 mm, and a maximum percentage of permanent deformation of 10.7 or more, but not more than 13.9". Leather with such characteristic values is not yet known.

The specified basis of genuine leather is different in that it has no greater extensibility than the usual level of skin extensibility, and has the ability to recover. On the surface of such a base made of genuine leather there is a layer of a coating film, and such a layer of a coating film shows the evenness and smoothness inherent only in natural skin when it is touched directly to natural skin.

Even when the front side of the aforementioned genuine leather base is ground (using sanding paper) and the scraped leather obtained is used as the base, the characteristics of the coating film of the present invention are still achievable, along with relatively positive results in other areas, since the characteristics the aforementioned genuine leather basics are still preserved.

Also, in some cases, positive results can still be obtained when conventional chrome tanning is applied, as explained above.

The present invention is also characterized by the formation on the surface of natural skin of a coating film.

A coating film is formed by forming the following four layers in the indicated order: (1) a primer layer and (2) a base coat layer are formed, and then on the surface of the base coat layer (3) a painted coating layer and (4) a topcoat layer.

(1) A primer layer is used to prevent the penetration of the basecoat material into the substrate, and also to enhance adhesion between the substrate and the basecoat layer. To form this layer, a composition consisting of resin, pigment, excipients and water is applied to the skin surface. The ratio between the solids content or the ratio of resin, pigment and auxiliary substances should be 40-70: 20-35: 10-30 (weight ratio based on the total content, taken as 100%). As a resin, a two-component polyurethane resin is used.

As a pigment, a pigment of the desired color is used. Examples of excipients include, but are not limited to, a surfactant, a thickening agent, and a regulatory agent.

The ratio of resin, pigment and excipients, on the one hand, and water, on the other hand, should be 40-70: 60-30 (weight ratio based on the total content, taken as 100%). The mixture, in its sole discretion, can be applied in the form of an aqueous solution using a brush or spray, or by coating with watering, or by coating with a roller. The flow rate of the applied composition is from 30 to 50 g / m ² and the coated surface is blown with hot air to evaporate the water. A high percentage of coating material penetrates the substrate, and the final film thickness is in the range of 4 to 6 microns.

(2) A basecoat layer is formed between the primer layer on the skin surface and the colored coating layer / topcoat layer to smooth out irregularities on the skin surface to create a stable base surface on which layers will form. This layer also connects and firmly bonds the primer layer and the painted coating layer / topcoat layer. This layer is also formed by applying to the skin surface a composition consisting of resin, pigment, excipients, tactile sensing agent, equalizer and water.

The ratio of solids or resin, pigment and excipients should be from 50-75: 10-20: 10-20 (weight ratio based on the total content, taken as 100%). As a resin, a two-component polyurethane resin is used. As a pigment, a pigment of the desired color is used. Examples of auxiliary substances include, but are not limited to, a surfactant, a thickening agent, a regulatory agent, and a matting agent. The ratio of resin, pigment, excipients, tactile sensing agent, and equalizer, on the one hand, and water, on the other hand, should be 60-70: 40-30 (weight ratio based on the total content, taken as 100% ) The mixture, in its sole discretion, can be applied in the form of an aqueous solution using a brush or spray, or by coating with watering, or by coating with a roller. The flow rate of the applied composition is from 35 to 55 g / m ² and the coated surface is blown with hot air to evaporate the water. The thickness of the obtained film is in the range from 7 to 10 microns.

(3) A colored coating layer, where a pigment or dye is present that tint the skin, is provided on top of the main coating when viewed from the front of the skin. Such a layer is also formed by applying to the skin surface a composition consisting of resin, pigment, excipients, a crosslinking agent, a tactile sensing agent, an equalizer and water.

The ratio of solids or resin, pigment, excipients, a crosslinking agent, a tactile sensing agent, and an equalizer should be 50-75: 10-20: 0-10: 3-10: 1-4: 1-4 (weight ratio based on the total content taken as 100%). As a resin, a two-component polyurethane resin is used. As a pigment, a pigment of the desired color is used. Examples of auxiliary substances include, but are not limited to, a surfactant, a thickening agent, and a regulatory agent. The ratio of resin, pigment, excipients, tactile sensing agent, and equalizer, on the one hand, and water, on the other hand, should be 70-80: 30-20 (weight ratio based on the total content, taken as 100% ) The mixture, in its sole discretion, can be applied in the form of an aqueous solution using a brush or spray, or by coating with watering, or by coating with a roller. The flow rate of the applied composition is from 30 to 45 g / m ² and the coated surface is blown with hot air to evaporate the water. The thickness of the obtained film is in the range from 7 to 10 microns.

(4) A topcoat layer is formed on the surface of the colored coating layer and is used to strengthen and strengthen the surface of the coating film, while attenuating the reflection of light due to the action of the added matting agent or matting agent, to prevent the surface of the coating film from becoming excessively glossy. When this layer is formed, the ratio of solids or resin, a small amount of pigment, a crosslinking agent, a tactile sensing agent, and an equalizer are adjusted to a ratio of 45-55: 0.1-3.0: 40: 8-15: 1- 4 (weight ratio based on the total content, taken as 100%). As a resin, a two-component polyurethane resin is used. Examples of excipients, among others, include a surfactant, a thickening agent and a regulatory agent. The ratio of resin, pigment, excipients, a crosslinking agent, a tactile sensing agent, and an equalizer, on the one hand, and water, on the other hand, should be 75-90: 25-10 (weight ratio based on the total content accepted for 100%). The mixture can be applied, at its discretion, in the form of an aqueous solution using a brush or aerosol, or by coating with watering, or by coating with a roller. The flow rate of the applied composition is from 30 to 45 g / m ² and the coated surface is blown with hot air to evaporate the water. The thickness of the obtained film is in the range from 10 to 15 microns.

In the present invention, a resin comprising a two-component polyurethane resin and a polyurethane resin, respectively, is used in the primer layer, the basecoat layer, the painted coating layer and the upper coating layer. More specifically, apply: (1) a two-component aliphatic polyurethane or (2) a copolymer of an acrylic polymer-urethane polymer, a polyurethane matting agent, etc., similar to the previously mentioned polyurethane resin.

(1) Two-component aliphatic polyurethane

A two-component water-based aliphatic polyurethane is used as a coating material.

When a two-component aliphatic polyurethane is used to form a coating film on natural skin, it is mixed and reacted with a water-based polyol and a hardener, which is a water-based aliphatic polyisocyanate.

Although a two-component aliphatic polyurethane is subject to the limitation that its processing, such as coating, must be performed within a certain period of time (viability limit), the method of processing natural leather proposed in the present invention requires only two to four hours or so, and in terms of practical work, there should not be any problem. The sizing coating film is stable and provides benefits such as no yellowing.

Water-based aliphatic polyisocyanate is produced as follows:

To produce a polyisocyanate mixture, an aliphatic isocyanate such as 1,4-diisocyanatebutane, 1,6-diisocyanatehexane, 1,5-diisocyanate-2,2-dimethylpentane, 2,2,4- or 2,4,4-trimethyl-1 is modified , 6-diisocyanatehexane, 1,10-diisocyanatedecane or another aliphatic isocyanate, to obtain a polyisocyanate containing a urea-diode group, an isocyanurate group, an urethane group, an alfanate group, a biuret group and / or an oxadiazine group, and then polymethoxymethoxy react with poly ethylene ksidnoe link (Japanese Patent №2961475).

As a water-based polyol, a diol containing a carboxyl group such as dimethylolbutanoic acid, dimethylolpentanoic acid, dimethylolheptanoic acid, dimethylolactanoic acid or dimethylolonanoic acid can be used. Among others, dimethylolbutanoic acid, dimethylolheptanoic acid and dimethylolonanoic acid, etc., are preferred from the viewpoint of production costs, and dimethylolbutanoic acid is most preferred. Such a diol containing a carboxyl group can be obtained using any known synthesis method, but it is usually obtained by aldol condensation of an alkyl aldehyde with formalin in the presence of a basic catalyst, after which the resulting condensation product is exposed to peroxide to oxidize the aldehyde group (Japanese Patent No. 3493796 laid out Japan Patent No. Hei 8-359884, etc.).

An aliphatic isocyanate (as described in the aforementioned Japanese Patent No. 2961475, etc.) can be used as a crosslinking agent.

Using the OH group contained in the aforementioned dimethylolalkanoic acid and tetramethylene polyether glycol, a coating material of a water-based polyurethane resin with a number average molecular weight (water-based polyurethane resin) of 18,000 to 35,000 or so is obtained (Japanese Patent No. 3493796, Patent Laid-Open Japan No. Hei 8-359884).

As for the number average molecular weight of the aforementioned polyurethane resin, a water based polyurethane resin with a number average molecular weight of from 12,000 to 20,000, or even 35,000, or 70,000 or so, is usually prepared. Here, "number average molecular weight" refers to the equivalent number average molecular weight of polystyrene obtained from the GPC measurement (gel permeation chromatography) of a tetrahydrofuran solution in which 1 weight percent polyurethane resin is dissolved. All molecular weight measurements referred to hereinafter were carried out in this way.

The molecular weights of the aliphatic polyisocyanate and polyol used in the reaction are controlled according to the molecular weight of the polyurethane required at the end.

A two-component water-based aliphatic polyurethane with a number average molecular weight of 10,000 or less can also be produced as follows:

The following two types of compositions are used or, in particular, (A) a composition consisting of (a) and (b), and (B) another composition consisting of (c) and (d), along with a (C) amine ( e) and (D) water. (C) and (D) act as chain terminating agents.

First, components (a) and (b), (c) and (d) are mixed and reacted with each other to obtain an NCO prepolymer, which is then mixed with component (e) and water to cause a reaction to produce a polyurethane containing 2 to 6 functional OH groups. The reaction is carried out at a temperature of approximately 70 ° C.

(A) A composition is used consisting of at least one type of polyol (a) with a number average molecular weight of from 1500 to 3000 g / mol, and at least one type of diol (b) with a molecular weight of from 61 to 499 g / mol.

More specifically, at least one type of polyol with a number average molecular weight of from 1500 to 3000 g / mol specified in paragraph (a) is the product of the interaction of a divalent alcohol and a dibasic carboxylic acid. The dibasic carboxylic acid may be, among others, succinic acid, adipic acid, suberinic acid, azelaic acid or sebacic acid.

The divalent alcohol may be, inter alia, ethylene glycol, 1,2- or 1,3-propylene glycol, 1,4-, 1,3- or 2,3-butylene glycol, 1,6-hexanediol, 1,8-octanediol , neopentyl glycol, 2-methyl-1,3-propanediol, diethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycol, dipropylene glycol, polypropylene glycol, dibutylene glycol or polybutylene glycol.

The above also applies to at least one type of diol with a molecular weight of 61 to 499 g / mol specified in paragraph (b), in particular ethylene glycol, 1,4-butanediol, 1,6-hexanediol, neopentyl glycol, trimethylpentanediol, propylene glycol, 1,3-propanediol, 1,4-cyclohexanedimethanol or any mixture thereof, but 1,4-butanediol is preferably used.

(B) A composition is used consisting of (c) an aliphatic diisocyanate with a molecular weight of 168 to 262 g / mol, and at least (d) one type of diol with at least one carboxyl or carboxylate group and a molecular weight less than 450 g / mol.

The aliphatic isocyanate of (c) is hexamethylenediisocyanate, butanediisocyanate or another isocyanate.

Regarding the diol of (d) with at least one carboxylic or carboxylate group, dimethylolacetic acid, 2,2-dimethylolpropionic acid, 2,2-dimethylolbutyric acid, 2,2-dimethylolpentanoic acid, dihydroxy succinic acid or the other are suitable 2 , 2-bis (hydroxymethyl) alkane carboxylic acid.

(C) (e) The amine introduces a terminal hydroxyl group, while the isocyanate first reacts with the amino group in the production method described below, in which the polyurethane dispersant of the present invention is involved. As the compound of (e), ethanolamine, propanolamine, N-methylethanolamine, diethanolamine or N, N, N'-Tris-2-hydroxyethylethylenediamine are used, but ethanolamine or diethanolamine, for example, is preferably used.

(D) (f) Water further increases the molecular weight of the dispersant after dispersion. The NH ₂ group is formed by reaction with the NCO group and additionally interacts with the NCO group to form a urea bond, and as a result, the molecular weight increases.

(E) The molar ratio of the polyol in component (a) to the sum of polyols (b) and (d) is from 1: 2 to 1: 3, while the molar ratio of the sum of polyols (a), (b) and (d) to isocyanate (c) is from 1: 1.2 to 1: 1.7, and the polyurethane contains from 2 to 4 OH functional groups.

(F) The number average molecular weight of the obtained polyurethane should preferably be from 2500 to 10000 g / mol (the foregoing is described in Japanese Patent Laid-Open No. 2000-119511).

(2) Two-component aliphatic polyurethane acrylic emulsion

In this invention, a two-component aliphatic polyurethane is made on a water basis.

When a two-component aliphatic polyurethane-acrylic emulsion is used to form a coating film on natural skin, it is mixed and reacted with a water-based polyol and a hardener, which is a water-based aliphatic polyisocyanate.

Although a two-component aliphatic polyurethane acrylic emulsion has a limited pot life and must be processed within a certain period of time, the process must be completed within six hours or so, and the sizing coating film is stable and provides benefits such as no yellowing.

Water-based aliphatic polyisocyanate is produced as follows:

To produce a polyisocyanate mixture, an aliphatic isocyanate such as 1,4-diisocyanatebutane, 1,6-diisocyanatehexane, 1,5-diisocyanate-2,2-dimethylpentane, 2,2,4- or 2,4,4-trimethyl-1 is modified , 6-diisocyanatehexane, 1,10-diisocyanatedecane or another aliphatic isocyanate, to obtain a polyisocyanate containing a urea-diode group, an isocyanurate group, an urethane group, an alfanate group, a biuret group and / or an oxadiazine group, and then polymethoxymethoxy react with poly ethylene ksidnoe link.

As a compound containing a hydroxyl group, which is reacted with the aforementioned water-based aliphatic polyisocyanate, a polyacrylate containing a hydroxyl group in a state dissolved in water or dispersed in water is used. Such a polyacrylate containing a hydroxyl group is used, as well as a polyester resin (based on an ester) containing an alkyd resin product to which alkylene oxide is added.

Generally, any aqueous solution or colloid of a water-based binder containing an isocyanate reactive group is suitable. If the polyisocyanate mixture of the present invention is used for this purpose, it is used in an amount corresponding to the equivalent ratio of the isocyanate group to the reactive group of the isocyanate, in particular the alcoholic hydroxyl group, usually from 0.5: 1 to 2: 1. The polyisocyanate mixture of the present invention can also be mixed with additives, such as a small amount of a monofunctional water-based varnish-based monofunctional binder, to improve adhesion to improve various characteristics.

(3) Use of polyurethane matting agent

A polyurethane matting agent is a coating agent used in a coating material that to some extent retains a slight gloss or appearance of a slight re-shine. Polyurethane matting agents, including a polyurethane mixture consisting of isocyanate and a hydroxy compound, are produced using unique methods. Accordingly, such polyurethane matting agents can be used as polyurethanes. For more details see published Japanese translation of international patent application PCT No. 2005-530868.

monomer I (monomer I, the basic organic structure of which does not contain a side alkyl group selected from the group consisting of aliphatic diisocyanate, hexamethylene diisocyanate and 4,4'-diisocyanatecyclohexylmethane);

monomer II (monomer II, the main organic structure of which contains at least one alkyl group selected from the group that includes monoisocyanate, diisocyanate, polyisocyanate and any mixture thereof);

Monomer III (divalent polyester polyol or polyether polyol);

monomer IV (divalent alcohol);

monomer V (hydroxycarboxylic acid);

monomer VI (polyamine);

monomer VII (amino alcohol); and

monomer VIII (monovalent polyether alcohol alkoxylated with alkylene oxide or monovalent polyether alcohol);

in which the amount of the introduced monomers I-VIII are such that:

(-OH +> N-H) / NCO the equivalent ratio of monomer III / monomers I + II is from 0.1 to 0.75;

(-OH +> N-H) / NCO the equivalent ratio of monomer IV / monomers I + II is from 0.2 to 0.8;

(-OH +> N-H) / NCO the equivalent ratio of monomer V / monomers I + II is from 0.05 to 0.5;

(-OH +> N-H) / NCO the equivalent ratio of monomer VI / monomers I + II is from 0 to 0.4;

(-OH +> N-H) / NCO the equivalent ratio of monomer VII / monomers I + II is from 0 to 0.4;

(-OH +> N-H) / NCO the equivalent ratio of monomer VIII / monomers I + II is from 0 to 0.2; and

(-OH +> N-H) / NCO equivalent ratio the total amount of monomers III-VIII / monomers I + II is from 0.80 to 1.25;

in which the total amount of monomer I and monomer II is from 50 to 100 mol% based on monomer I, while from 50 to 2000 mmol of carboxy groups in monomer V, introduced per 1 kg of polyurethane A into the water-based preparation, in the form of anions (published Japanese translation of international patent application PCT No. 2005-530868).

Such a polyurethane preparation contains insoluble grains in a polyurethane matrix, where the average diameter of such grains should be from 1 to 20 μm, or preferably from 2 to 15 μm, or more preferably from 3 to 10 μm, or most preferably from 3 to 7 μm (paragraph 0042 in the aforementioned Japanese Patent Publication). The polyurethane dispersant may contain commercially available adjuvants and additives, such as a foaming agent, antifoam, emulsifier, viscosity regulator, humectant or thixotropic agent, and a coloring agent, such as a dye or pigment.

Such a water-based polyurethane preparation should preferably be used on the skin, since it further reduces gloss and increases wear resistance, water resistance, elasticity, the appearance of a slight re-shine, dark color and a pleasant, warm and soft tactile sensation.

(4) As a crosslinking agent for curing said polyurethanes, various polyisocyanates, in particular diisocyanates, where at least one or more diisocyanates selected from tolylenediisocyanate, hexamethylene diisocyanate and methylenediisocyanate are preferably used, can be used. In particular, such crosslinking agents should be used in the form of crosslinking agents that are modified and contain many hydroxyl groups, such as trimethylolpropane, or as crosslinking agents such as isocyanurate, in which three molecules of the diisocyanate compound are combined. Such crosslinking agents bind to functional groups, etc., contained in the aforementioned binder to crosslink resins. Ideally, the content of crosslinking agents should be between 10 and 30 parts by weight, based on 100 parts by weight of the binder. When curing a thermoplastic resin or resins, a general rule of thumb is to allow the resin-based mixture to remain stationary for 12 hours at room temperature.

According to the present invention, the following coating film is formed on the basis of genuine leather.

More specifically, a colored coating layer and a topcoat layer are formed using various resin-based components selected according to the shape of the stress-strain curve, and such various resin-based components are combined to form each layer.

To form a colored coating layer, a hard component (resin, whose 10% modulus is greater than 2.3, but not more than 3.0), a resin containing a two-component polyurethane resin and polyurethane resin is mixed with a soft component (resin, whose 10% modulus is greater than 0, 0, but not more than 1.0) resin containing a two-component polyurethane resin and polyurethane resin.

Then, a topcoat layer is formed on top of the painted coating layer by mixing the middle component (resin, whose 10% modulus is greater than 1.0, but not more than 2.3), a resin containing a two-component polyurethane resin and polyurethane resin, and a soft component (resin, whose 10 % module is greater than 0.0, but not more than 1.0) of a resin containing a two-component polyurethane resin and a polyurethane resin.

It should also be noted that each layer is formed, taking into account the amount of each component, as follows.

The aforementioned colored coating layer is formed by mixing from 48 to 90 weight percent of the rigid component (resin, whose 10% modulus is greater than 2.3 but not more than 3.0) of a resin containing a two-component polyurethane resin and polyurethane resin, and from 52 to 10 weight percent soft component (resin, whose 10% modulus is more than 0.0, but not more than 1.0) of a resin containing a two-component polyurethane resin and a polyurethane resin; while the aforementioned topcoat layer is formed by mixing from 15.0 to 35.0 weight percent of the middle component (resin, whose 10% modulus is greater than 1.0 but not more than 2.3) of a resin containing a two-component polyurethane resin and polyurethane resin, and from 65.0 to 85.0 weight percent of the soft component (resin, whose 10% modulus is greater than 0.0, but not more than 1.0), a resin containing a two-component polyurethane resin and a polyurethane resin.

In the present invention, a colored coating layer is formed by mixing a hard component (resin, whose 10% modulus is greater than 2.3, but not more than 3.0) of a resin containing a two-component polyurethane resin and polyurethane resin, and a soft component (resin, whose 10% modulus more than 0.0, but not more than 1.0) resin containing a two-component polyurethane resin and polyurethane resin.

A topcoat layer is formed on top of the painted coating layer by mixing the middle component (resin, whose 10% modulus is greater than 1.0, but not more than 2.3), a resin containing a two-component polyurethane resin and polyurethane resin, and a soft component (resin, whose 10% a module greater than 0.0, but not more than 1.0) of a resin containing a two-component polyurethane resin and a polyurethane resin.

As described above, the aforementioned resins are divided into three components: a hard component, a middle component and a soft component, of which the hard and soft components are combined (a colored coating layer), while the middle and soft components are also combined (a top coating layer), the formation of new laminated layers, while creating a layered structure with new characteristics that differ from the characteristics of conventional layered structures. Such a structure differs from coating films, whose characteristics are limited by the characteristics described by conventional stress-strain curves.

It is important that it is necessary to select suitable resins in accordance with the above components, and the classification results of suitable resins from this point of view are given below. You only need to select and use the desired resins from such candidates at your own discretion.

Of the resins containing a two-component polyurethane resin and a polyurethane resin, the following are specific products corresponding to the hard component of the resin containing a two-component polyurethane resin and a polyurethane resin:

ASTACIN MATTING MA, ASTACIN FINISH PF, ASTACIN FINISH PE, ASTACIN FINISH PFM, ASTACIN TOP LH (all manufactured by BASF), AQUALEN TOP 2006 B (manufactured by CLARIANT), FINISH BB, BAYDERM FINISH 61UD, AQUADERM FINISH HAT, BAYDERM FINISH DLH , BAYDERM FINISH 71UD, BAYDERM FINISH 80UD, BAYDERM FINISH 95UD (all manufactured by LANXESS), WT-7370, WT-2511 (both manufactured by STAHL), HUX-561M1 (manufactured by ADEKA).

Of the resins containing the two-component polyurethane resin and the polyurethane resin, the following are specific products corresponding to the middle component of the resin containing the two-component polyurethane resin and the polyurethane resin:

ASTACIN FINISH PUMN (manufactured by BASF), AQUALEN TOP DP-2055, AQUALEN TOP 2002.A, MELIO PROMUL 68.A, MELIO PROMUL 66.A, AQUALEN TOP D-2017 (all manufactured by CLARIANT), LCC BINDER-UB- 1770 (manufactured by DIC), BAYDERM RM FINISH 85UD, BAYDERM FINISH 65UD, emulsion HYDRHOLAC CR-5, dispersion HYDRHOLAC UD-2 (all manufactured by LANXESS), WT-13-492, WT-13-485, RU-13045, RU-6125, WT-2586 (all manufactured by STAHL).

Of the resins containing a two-component polyurethane resin and a polyurethane resin, the following are specific products corresponding to the soft component of the resin containing a two-component polyurethane resin and a polyurethane resin:

ASTACIN FINISH PUM, ASTACIN FINISH SUSI, NOVOMATT GG (all BASF products), AQUALEN TOP 2003.A, AQUALEN TOP 2007.A, AQUALEN TOP D-2012.B, AQUALEN TOP D-2019, PROMUL 95.A (all production CLARIANT companies), LCC BINDER-UB-1450, UB-1650F (both manufactured by DIC), BAYDERM FINISH 60UD, BAYDERM BOTTOM 51UD, BAYDERM BOTTOM DLV, BAYDERM FINISH 50UD, BOTTOM CTR, HYDRHOLAC 3089, HYDRHOLACOLAC H89 (all manufactures of LANXESS company), RH-6663, RH-6677, RU-3906, WT-13-486, WT-2524 (all productions of STAHL company).

Each component is described below by considering the corresponding specific stress-strain curve.

The shape of the stress-strain curves can be characterized by a value of 10% modulus. A 10% modulus is the stress required to create a 10% strain, or a measure of the tensile force leading to a 10% elongation.

If the 10% modulus of a given resin is greater than the 10% modulus of another resin, this means that the first resin must be stretched with more force and less stretched than the second resin. Resins can be grouped according to their tensile strength.

When resins containing a two-component polyurethane resin and a polyurethane resin are classified as different components, the question of whether to use one component or several components of a resin containing a two-component polyurethane resin and a polyurethane resin is arbitrarily decided. Since an increase in the number of components most likely involves the use of more subtle adjustments, it is difficult to expect that all components will change in the same way and, therefore, a rash increase in components is impractical. Instead, it is necessary to discuss the types of components and their suitable contents.

A colored coating layer is formed by mixing a rigid two-component polyurethane component (resin, whose 10% modulus is more than 2.3, but not more than 3.0), and a soft two-component polyurethane component (resin, whose 10% module is more than 0.0, but not more than 1,0).

The combination of resins corresponding to hard and soft components is described below.

Obviously, when the components are combined, the total number of constituent resins is more important than the number of components.

If only one two-component aliphatic polyurethane resin (whose 10% modulus is 2.88; see FIG. 3) is used as the aforementioned matting agent, its content should be adjusted to 78 weight percent (in the case of Example 11).

A rigid component (resin, whose 10% modulus is greater than 2.3, but not more than 3.0), of a resin containing a two-component polyurethane resin and a polyurethane resin, which is used to form a colored coating layer, is formed by mixing a two-component aliphatic polyurethane resin (whose 10% the module is 2.88; see FIG. 3), which is a matting agent, and another two-component aliphatic polyurethane resin (whose 10% modulus is 2.77; see FIG. 4).

When a two-component aliphatic polyurethane resin (whose 10% modulus is 2.88; see FIG. 3) used as a matting agent is combined with another two-component aliphatic polyurethane resin (whose 10% modulus is 2.77; see FIG. 4 ), the total amount of both resins should be brought to 70 weight percent (in the case of examples 2-6).

The soft component of the resin containing a two-component polyurethane resin and a polyurethane resin, which is used to form a colored coating layer, is formed by mixing aliphatic polyurethane (whose 10% module is 0.54; see figure 5) and two-component aliphatic polyurethane (whose 10% module equal to 0.30; see Fig.6). In examples 2-6, the total content of both resins was adjusted to 30 weight percent.

In examples 7-10, the content of the components of the topcoat layer is fixed, and the percentages of the hard component of the resins and the soft component of the resins forming the colored coating layer are changed. Thus, by calculating the values, it is possible to make the ranges of the components of the painted coating layer more obvious.

In example 7, the content of the hard component is 90 weight percent, while the content of the soft component is 10 weight percent;

in example 8, the content of the hard component is 80 weight percent, while the content of the soft component is 20 weight percent;

in example 9, the content of the hard component is 70 weight percent, while the content of the soft component is 30 weight percent; and

in example 10, the content of the hard component is 60 weight percent, while the content of the soft component is 40 weight percent.

The colored coating layer contains from 48 to 90 weight percent of the hard component (resin, whose 10% modulus is more than 2.3, but not more than 3.0) of a resin containing a two-component polyurethane resin and polyurethane resin, and from 52 to 10 weight percent of the soft component (resin, whose 10% modulus is greater than 0.0, but not more than 1.0) a resin containing a two-component polyurethane resin and a polyurethane resin, where all the mixing results were within the above ranges.

To form a topcoat layer, the middle component (resin, whose 10% modulus is greater than 1.0, but not more than 2.3), is a resin containing a two-component polyurethane resin and polyurethane resin, or the middle component of the resin (resin, whose 10% module is a two-component polyurethane resin more than 1.0, but not more than 2.3) are mixed with a soft two-component polyurethane component (whose 10% modulus is more than 0.0, but not more than 1.0).

As a middle component (resin, whose 10% modulus is greater than 1.0, but not more than 2.3), a resin containing a two-component polyurethane resin and a polyurethane resin, a two-component aliphatic polyurethane resin is used (whose 10% module is 1.89; see Fig. 8). In examples 2-6, the content varies from 7.5 to 15, 25, 30 and 37.5 weight percent. In examples 7-10, the content of the middle component of the topcoat layer was adjusted to 25 weight percent.

In all cases, the content of the middle component of the resin containing a two-component polyurethane resin and a polyurethane resin that forms the topcoat layer was in the range from 15.0 to 35.0 weight percent.

The soft component (resin, whose 10% modulus is greater than 0.0, but not more than 1.0), a resin containing a two-component polyurethane resin and a polyurethane resin, which is used to form the topcoat layer, is formed by mixing a two-component aliphatic polyurethane resin (matting resin) (whose 10% modulus is 0.67; see Fig. 9), another two-component aliphatic polyurethane resin (whose 10% modulus is 0.54; see Fig. 10) and an acrylic-urethane polymer copolymer (whose 10% modulus is 0.11; see Fig. 11).

In Example 2, the total content is 85 weight percent;

In example 3, the total content is 70 weight percent;

In example 4, the total content is 75 weight percent;

In example 5, the total content is 70 weight percent;

In example 6, the total content is 62.5 weight percent;

In examples 7-10, the total content is 75 weight percent; and in Example 11, the content of each middle component is 25 weight percent, with a total content of three components totaling 75 weight percent.

In all cases, the total content of each of the soft two-component polyurethane components containing polyurethane resin (resin, whose 10% modulus is more than 0.0, but not more than 1.0) was in the range from 65.0 to 85.0 weight percent.

Regarding the percentage of each component forming the colored coating layer and the topcoat layer, positive results were obtained when the percentage was within each suitable range mentioned above.

Once the percentages deviate from such ranges, the desired topcoat layer cannot be obtained.

As soon as the coating film is formed, tracking, felting in the drum, vibration processing, pre-pressing, etc. are carried out if necessary, after which the skin is sent to the inspection stage and examined.

The steps described above are used to form a coating film based on it.

The basis is described below. More specifically, the skin production method of the present invention is described, in which genuine leather, providing excellent characteristics not previously attainable, is produced using the tanning step of the skin, as well as the stages of neutralization, retanning, dyeing and fatliquoring. The skin of the present invention, providing excellent characteristics not previously achievable, and produced using the tanning step of the skin, as well as the stages of neutralization, retanning, dyeing and fatliquoring, are described below (as described in Japanese Patent Application No. 2007-170359). In the present invention, the most positive results can be obtained by forming a coating film on the skin obtained above. The following explanation mainly discusses the stages by which the skin base is obtained, which is an indispensable condition for obtaining such most positive results. In the above invention, suitable skin is provided by the following two inventions. The invention 1 described below provides natural skin that is most suitable for use in the present invention. The invention 2 also provides good skin. Of course, this includes the type of good skin on which the present invention is based.

The skin of the present invention, providing excellent characteristics not previously achievable, and produced by the tanning step of the skin, as well as the stages of neutralization, retanning, dyeing and fatliquoring are described below (as described in Japanese Patent Application No. 2007-170359).

The invention 1 is described below.

Genuine leather obtained with:

(1) pretreatment steps before tanning leather;

(2) a tanning step using glutaraldehyde as a tanning agent;

(3) the stage in which the skin is tanning using a tanning agent consisting of a synthetic tanning agent, a resin and an aluminum compound, where the synthetic tanning agent consists of: (A) a condensation product of aromatic sulfonic acid and formaldehyde or aromatic sulfonic acid and an aromatic sulfonic acid condensation product and formaldehyde, (B) a methylene-containing cyclocondensation product of aromatic sulfonic acid and a hydroxyaromatic compound, or aromatic sulfonic acid and methylene-containing a cyclocondensation product of aromatic sulfonic acid and a hydroxyaromatic compound, and (C) glyoxal, while the resin consists of: (A) a polymer or a mixture of acrylic acid, methacrylic acid, an ester of acrylic acid or an ester of methacrylic acid, or a copolymer of any combination the foregoing, or a mixture of such copolymers; and (B) a polycondensation product of melamine and formaldehyde, where the skin is tanning using a tanning agent of the aforementioned composition, after which the skin is dyed, and then subjected to fatliquoring using a lubricating agent consisting of: (A) synthetic oil and natural oil, or (B) mixed oils containing synthetic oil and a natural component; and

(4) post-retreatment post-processing steps.

The invention 2 is described below.

Genuine leather obtained with:

(1) pretreatment steps before tanning leather;

(2) a tanning step using glutaraldehyde as a tanning agent;

(3) a stage in which the skin is tanning using a tanning agent consisting of a synthetic tanning agent and a resin, where the synthetic tanning agent consists of: (A) a condensation product of aromatic sulfonic acid and formaldehyde or aromatic sulfonic acid and a condensation product of aromatic sulfonic acid and formaldehyde; (B) a methylene-containing cyclocondensation product of aromatic sulfonic acid and a hydroxyaromatic compound or aromatic sulfonic acid and a methylene-containing cyclocondensation product of aromatic sulfonic acid and a hydroxyaromatic compound; and (C) glyoxal; while the resin consists of: (A) a polymer or mixture of acrylic acid, methacrylic acid, an ester of acrylic acid or an ester of methacrylic acid, or a copolymer of any combination of the foregoing, or a mixture of such copolymers; and (B) a polycondensation product of melamine and formaldehyde, where the skin is tanning using a tanning agent of the aforementioned composition, after which it is dyed and then fattened using a lubricating agent consisting of: (A) synthetic oil and natural oil; or (B) a blended oil containing a synthetic oil and a natural component; and

(4) post-retreatment post-processing steps.

In the invention 1, which is described above, the aforementioned retanning device contains from 20 to 30 weight percent of synthetic tanning agent, from 13 to 25 weight percent of resin and from 0.7 to 4.0 weight percent of aluminum per 100 weight percent of scraped skin; where the aforementioned synthetic tanning agent contains: (A) from 0.45 to 0.50 of a condensation product of aromatic sulfonic acid and formaldehyde, or of aromatic sulfonic acid and a condensation product of aromatic sulfonic acid and formaldehyde; (B) from 0.38 to 0.43 of a methylene-containing cyclocondensation product of aromatic sulfonic acid and a hydroxyaromatic compound, or of an aromatic sulfonic acid and a methylene-containing cyclocondensation product of aromatic sulfonic acid and a hydroxyaromatic compound; and (C) from 0.10 to 0.15 glyoxal (all expressed in weight fractions giving a total of 1.00); while the above resin contains: (A) 0.67 to 0.72 polymer or mixture of acrylic acid, methacrylic acid, ester of acrylic acid or ester of methacrylic acid, or a copolymer of any combination of the foregoing, or a mixture of such copolymers; and (B) 0.28 to 0.33 polycondensation product of melamine and formaldehyde (both given in weight fractions giving a total of 1.00) and a lubricating agent consisting of: (A) synthetic oil and natural oil, or ( B) a mixed oil containing synthetic oil and a natural component, based on 15-19 weight percent per 100 weight percent of scraped skin.

The characteristics of the skin according to the invention described above 1 include the characteristics of a sample taken from a piece of skin obtained after the post-retreatment post-processing step, where the stiffness / softness is 5.0 mm or more and the maximum percentage of permanent deformation is 10% or less.

In invention 2, as described above, the aforementioned retanning agent contains from 20 to 30 weight percent synthetic tanning agent and from 13 to 25 weight percent resin (both based on 100 weight percent scraped leather), where the aforementioned synthetic tanning agent contains: (A) from 0 45 to 0.50 of the condensation product of aromatic sulfonic acid and formaldehyde or aromatic sulfonic acid and of the condensation product of aromatic sulfonic acid and formaldehyde; (B) from 0.38 to 0.43 of a methylene-containing cyclocondensation product of aromatic sulfonic acid and a hydroxyaromatic compound, or of an aromatic sulfonic acid and a methylene-containing cyclocondensation product of aromatic sulfonic acid and a hydroxyaromatic compound; and (C) from 0.10 to 0.15 glyoxal (all expressed in weight fractions giving a total of 1.00), while the above resin contains: (A) from 0.67 to 0.72 polymer or mixture acrylic acid, methacrylic acid, an ester of acrylic acid or an ester of methacrylic acid, or a copolymer of any combination of the foregoing, or a mixture of such copolymers; and (B) from 0.28 to 0.33 of a polycondensation product of melamine with formaldehyde (in both cases the values are presented in weight fractions giving a total of 1.00) and a lubricating agent consisting of: (A) synthetic oil and natural oil , or (B) a mixed oil containing synthetic oil and a natural component at the rate of 15-19 weight percent per 100 weight percent of scraped skin.

The characteristics of the skin according to the aforementioned invention 2 include the characteristics of a sample taken from a piece of skin obtained after the post-retreatment post-processing step, where the stiffness / softness is 4.42 mm or more, but not more than 4.90 mm, and the maximum percentage of residual strain is 10.7 or more, but not more than 13.9.

Both of the two aforementioned inventions are described by the present inventors in Japanese Patent Application No. 2007-170395.

A specific production method is described below.

To obtain genuine leather using the stage of tanning the skin, as well as the stages of neutralization, retanning, dyeing and fatliquoring, the following processes were carried out.

(1) Pre-treatment performed before tanning is described below.

The skin taken from the skin of an adult cattle is soaked in water, then washed with water and removed, after which sticky substances (such as fat and meshes) are mechanically removed from the inside and the resulting skin is poured into an ash liquid to dissolve hair on the skin surface , then dirt is removed from the surface of the skin and the skin is impregnated with fly ash to loosen the fibers, after which the skin is divided into the front part (front side of the skin) and the mesure part (reverse side of the skin) with a tape knife. At this stage, keratin was removed from the epidermal layer and elastin from the lower layer. The resulting skin is in a state where all parts that are not collagen fibers are removed from its structure. Such traditional methods and means of processing, which are already widely known, can be chosen at your own discretion.

(2) The tanning step is described below.

The front surface and the medial side obtained in the previous stage are anesthetized by neutralizing and removing the ash fluid used to soak the skin in the previous stage (spray water with a pH adjusted and carry out another process to accelerate the action of the proteolytic enzyme; the water used in this process has a temperature in the range from 30 to 35 ° C and contains sodium hydrosulfite containing from 1 to 2% ammonium chloride, etc.), and then the skin is softened in the presence of a proteolytic enzyme (apply soft itel mixed with pancreatin or another enzyme) (in this method, the skin is impregnated with water containing a suitable degrading enzyme using water containing from 0.8 to 1.2% of this enzyme preparation and 0.5% ammonium chloride), followed by collagen the fabric softens, the enzyme is removed, followed by tanning using a tanning agent (impregnated with water containing a suitable tanning agent).

Glutaraldehyde is used as a tanning agent. Apply from 1 to 10 weight percent glutaraldehyde based on skin weight. In this method, a tanning agent is used with water at approximately 30 ° C, at a pH of from 1.8 to 5 and a temperature of from 20 ° C to 30 ° C, where the processing time is from 8 to 12 hours. The heat shrink temperature when glutaraldehyde is used is 65 to 70 ° C.

Successive processes from desalination to softening and tanning are carried out in a single drum for an extended period. After the tanning process is completed, the skin is squeezed and then stretched to provide the skin thickness of the required level, then the back side is scraped to adjust the thickness (scraping), followed by cutting off unnecessary parts on the periphery of the skin (cutting).

(3) The “retanning” step is described below.

The skin obtained in the tanning step is retaned using a retanning agent consisting of a synthetic tanning agent and a resin, after which the skin is dyed and then fattened by adding a lubricating agent. The retanning, dyeing and fatliquoring is carried out in the same drum, where each process is carried out for a certain period of time.

The aforementioned retanning device contains from 20 to 30 weight percent synthetic tanning agent and from 13 to 25 weight percent resin based on 100 weight percent scraped leather.

Before retanning, they are convinced whether the previous neutralization was successful or not. More specifically, a solution with a pH indicator is dripped onto a skin cross section and the color of the layer changes. Roughly, the pH level of the excellent facial skin should be from about 5 to 6 for the surface layer and from about 3 to 4 for the inner layer. At the stage of retanning, the used synthetic tanning agent or other tanning agent should be in the form of an aqueous solution containing from 50 to 200% of such tanning agent based on the weight of the applied skin.

The pH range should be from 3.0 to 8.0, or preferably from 3.5 to 6.5. Preferably, the retanning step should last from 1.5 to 24 hours, or more preferably from 2 to 8 hours.

The above synthetic tanning agent contains: (A) from 0.45 to 0.50 a condensation product of aromatic sulfonic acid and formaldehyde, or an aromatic sulfonic acid and a condensation product of aromatic sulfonic acid and formaldehyde, (B) from 0.38 to 0.43 methylene-containing product cyclocondensation of aromatic sulfonic acid and hydroxyaromatic compound, or aromatic sulfonic acid and methylene-containing product of cyclocondensation of aromatic sulfonic acid and hydroxyaromatic compound I, and (C) from 0.10 to 0.15 of glyoxal (all expressed in weight fractions, giving a total of 1.00).

In addition, the aforementioned aromatic sulfonic acid and the condensation product of aromatic sulfonic acid and formaldehyde (limited to a total weight fraction of 1.0) are a mixture containing more than 0, but not more than 0.3 (weight fraction) of aromatic sulfonic acid and less than 1-0 , 7 (weight fraction) of the condensation product of aromatic sulfonic acid and formaldehyde.

In addition, the aforementioned aromatic sulfonic acid and the methylene-containing cyclocondensation product of aromatic sulfonic acid and a hydroxyaromatic compound (limited to a total weight fraction of 1.0) are a mixture containing more than 0 but not more than 0.3 (weight fraction) of aromatic sulfonic acid and less than 1 -0.7 (weight fraction) of a methylene-containing cyclocondensation product of aromatic sulfonic acid and a hydroxyaromatic compound.

The aforementioned aromatic sulfonic acid is monosulfone, disulfone or a salt thereof, obtained by sulfonation of an aromatic compound selected from the group consisting of, among others, benzene, phenylbenzene, diphenyl ether and naphthalene. The use of such aromatic sulfonic acid as a retanning agent is also known (German patent No. 578578, US patent No. 2315951, US patent No. 3906037, Japanese patent laid out No. Sho 56-28300).

Specific examples include naphthalenesulfonic acid, phenolsulfonic acid, sulfonated ditolyl ether, 4,4'-dihydroxydiphenylsulfone, sulfonated diphenylmethane, sulfonated biphenyl, sulfonated terphenyl or benzenesulfonic acid, naphthalene disulfonic acid, phenol disulfonated sulfonic acid 4, diphenyl disulfonic acid -dihydroxydiphenyldisulfone, disulfonated diphenylmethane, disulfonated biphenyl, disulfonated terphenyl or benzene disulfonic acid.

Such condensation products of said phenolsulfonic acids containing phenolsulfonic acids and formaldehyde can be used. More specifically, among others, Synectan PN, Synectan WF (both from Zeneca), Tanigan LH (from Bayer) and Forestane DW (from Forest) can be used.

The aforementioned naphthalenesulfonic acid condensation products containing naphthalenesulfonic acids and formaldehyde may also be used. More specifically, Synectan ACNN (manufactured by Zeneca) can be used.

Other examples include other mixtures of condensation products of such phenolsulfonic acids containing phenolsulfonic acids and formaldehyde, or condensation products of naphthalenesulfonic acids containing naphthalenesulfonic acids and formaldehyde such as Tanigan 3LN (manufactured by Bayer), Basyntan DLX (manufactured by BASF), Forestane LC (manufactured by Forest) and others that are tanning agents containing PSA and NSA.

The weight average molecular weight of the aforementioned naphthalenesulfonic acid condensation product containing naphthalenesulfonic acid and formaldehyde, or the phenolsulfonic acid condensation product containing phenolsulfonic acid and formaldehyde, is from 400 to 4000 for the first product, and from 200 to 2000 for the latter product.

The aforementioned aromatic sulfonic acid is monosulfone, disulfone or a salt thereof, obtained by sulfonation of an aromatic compound selected from the group consisting of, among others, benzene, phenylbenzene, diphenyl ether and naphthalene. The use of such aromatic sulfonic acid as a retanning agent is also known (German patent No. 578578, US patent No. 2315951, US patent No. 3906037, Japanese patent laid out No. Sho 56-28300).

Specific examples include naphthalenesulfonic acid, phenolsulfonic acid, sulfonated ditolyl ether, 4,4'-dihydroxydiphenylsulfone, sulfonated diphenylmethane, sulfonated biphenyl, sulfonated terphenyl or benzenesulfonic acid, naphthalene disulfonic acid, phenol disulfonated 4-sulfonated sulfonic acid -dihydroxydiphenyldisulfone, disulfonated diphenylmethane, disulfonated biphenyl, disulfonated terphenyl or benzene disulfonic acid.

Such condensation products of said phenolsulfonic acids containing phenolsulfonic acids and formaldehyde can be used. More specifically, Synectan PN, Synectan WF (both manufactured by Zeneca), Tanigan LH (manufactured by Bayer) and Forestane DW (manufactured by Forest) can be used, among others.

The aforementioned naphthalenesulfonic acid condensation products containing naphthalenesulfonic acids and formaldehyde may also be used. More specifically, Synectan ACNN (manufactured by Zeneca) can be used.

Other examples include other mixtures of condensation products of such phenolsulfonic acids containing phenolsulfonic acids and formaldehyde, or condensation products of naphthalenesulfonic acids containing naphthalenesulfonic acids and formaldehyde such as Tanigan 3LN (manufactured by Bayer), Basyntan DLX (manufactured by BASF), Forestane LC (manufactured by Forest) and others that are tanning agents containing PSA and NSA.

The weight average molecular weight of the aforementioned naphthalenesulfonic acid condensation product containing naphthalenesulfonic acid and formaldehyde, or the phenolsulfonic acid condensation product containing phenolsulfonic acid and formaldehyde, is from 400 to 4000 for the first product, and from 200 to 2000 for the latter product.

The methylene-containing cyclocondensation product of aromatic sulfonic acid and hydroxyaromatic compound is described below.

The hydroxyaromatic compound is phenol, cresol or dihydroxydiphenylmethane. The methylene-containing product of the cyclocondensation of the hydroxyaromatic compound is the condensation product of the aforementioned hydroxyaromatic compound and formaldehyde. It is a condensation product of sulfonated phenol and formaldehyde, a condensation product of sulfonated phenol or cresol and formaldehyde, a formaldehyde condensation product of 4,4'-dihydroxydiphenyl sulfone and (hydroxy) arylsulfonic acid, a formaldehyde condensation product of sulfone-containing aromatic hydroxy compound, anhydryl formaldehyde and an aryl phenolsulfonic acid (Japanese Patent Laid-open No. Hei 8-232000, Japanese Patent Laid-open No. Hei 10-101757).

Glyoxal is a compound used as a tanning agent according to the present invention, as well as a processing aid in fiber processing, a processing aid in paper processing, a soil hardener or other organic synthesis intermediate.

Among the methods for the production of glyoxal, it is well known one in which the corresponding alcohol compound, glycolaldehyde, etc. are oxidized. Among such methods, a method of oxidizing and dehydrogenating ethylene glycol in the presence of a silver catalyst is known (Japanese Examined Patent No. Sho 61-54011, Japanese Patent Laid-open No. Hei 6-329575). Any known substance produced as described above may be purchased and used.

The above resin contains: (A) 0.67 to 0.72 polymer or mixture of acrylic acid, methacrylic acid, ester of acrylic acid or ester of methacrylic acid, or a copolymer of any combination of the above polymers, or a mixture of such copolymers; and (B) from 0.28 to 0.33 of a polycondensation product of melamine with formaldehyde (in both cases, the values are presented in weight fractions giving a total of 1.00).

A polymer based on acrylic acid, methacrylic acid, an ester of acrylic acid or an ester of methacrylic acid is a polymer obtained by polymerizing monomers selected from the group consisting of acrylic acid, methacrylic acid, acrylic ester and methacrylic ester or a mixture of such polymers.

A copolymer of acrylic acid, methacrylic acid, acrylic ester or methacrylic ester is a copolymer consisting of monomers selected from the group consisting of acrylic acid, methacrylic acid, acrylic ester and methacrylic ester or a mixture of such copolymers .

The copolymer of acrylic acid, methacrylic acid, ester of acrylic acid or ester of methacrylic acid also includes a graft polymer obtained by polymerizing monomers selected from the group consisting of acrylic acid, methacrylic acid, acrylic ester and methacrylic ester acid, and subsequent polymerization of the obtained polymerized monomers.

The weight average molecular weight of such a polymer should be from 1000 to 250,000, or more preferably from 1,000 to 100,000. Any commercially available product can be purchased and used.

Such resins are blended to add viscoelastic properties (rubber properties) and also add hardness and tensile strength. It is believed that such acrylic resins should add elasticity to the skin and significantly contribute to improving the degree of its permanent deformation (ease of restoration of the original form after stretching). However, it is undesirable to use a larger than necessary amount of acrylic resins, in terms of their characteristics, since such an effect on the characteristics of the skin will be too large. Accordingly, it is important to maintain the content of acrylic resins in the above range.

The use of acrylic acid or methacrylic acid or a mixture thereof, an ester of acrylic acid or an ester of methacrylic acid, or a polymer based on acrylic acid and / or methacrylic acid, etc. as tanning agent, it is already known thanks to the publication of Japanese Patent Laid-Open No. Sho 56-59900, Japanese Patent Laid-Open No. Sho 56-161500, etc. However, these substances are generally not stable enough, and it was noted that their use leads to the appearance of lines, cracks, etc., formed on the surface of the skin (Japanese Patent Laid-Open No. Hei 4-89900, Japanese Patent Laid-open No. Hei 9-95700), and therefore, it is necessary to combine them according to the present invention.

Polycondensation product of melamine and formaldehyde

The use of a resin consisting of a condensation product of melamine and formaldehyde is described in Japanese Patent Laid-Open No. Sho 63-89600, Japanese Patent Laid-open No. Sho 63-89599, etc.

The effective ratio of melamine to formaldehyde is from 1: 1.5 to 1: 6 or so.

It is also effective to use a mixture of resins or a mixed resin consisting of melamine and formaldehyde resins, or melamine-formaldehyde resins forming anionic resins.

It is also effective to esterify at least one of melamine and formaldehyde using glycol ether or alkyl glycol ether.

Melamine resins are expected to add such characteristics, resulting in skin flexibility, although the result of combining the acrylic resin with the melamine resin was effective and led to a favorable result of the present invention.

At the stage of dyeing, the skin is stained with dye.

In the dyeing step, a suitable dye or pigment is used according to the desired color.

The skin obtained using the aforementioned processing method is stained using a water-based acid dye. Such a water-based acidic dye consists of several components, including a water-based medium and a dye.

The term "water-based medium" refers to a mixture of water and an aqueous solvent consisting of water and alcohol, etc. As the dye, any type of dye that can tint the skin, such as an acid dye or a reactive dye, can be used.

At the fatliquoring stage, the skin is treated with a lubricating agent.

The fatliquoring step is a process that accompanies the dyeing step after retanning, and is carried out in order to add the necessary elasticity to the leather product by treating it with a sizing agent called a “greasing agent”. Such a lubricating agent is selected so that it easily penetrates inward throughout the skin.

The skin treated in the fatliquoring step after the dyeing step is wet and the water present between the fibers in the fiber bundles allows the fibers to remain elastic. However, as soon as such water dries, the mentioned fibers stick together, and both the fibers and the skin tissue will harden. Accordingly, prior to drying, it is effective to pretreat the skin using a lubricant that prevents the fibers from sticking together. There is also a need to add functions to the skin, such as a skin fiber protection function (water repellent, waterproof property), improved tactile sensation and bulkiness. At the fatliquoring stage, this goal is achieved by using a lubricating agent.

The skin is treated with a lubricating agent for 1 to 6 hours at a temperature of 25 to 50 ° C.

The littering agent is added in an amount of 15 to 19 weight percent, based on 100 weight percent of scraped skin.

As a lubricating agent, synthetic oil, natural oil or a mixture of synthetic oil and natural oil components are used (the weight ratio of these two should be 0.4-0.6: 0.6-0.4). One example of a synthetic oil is sulfonated oil, or in particular alkyl sulfonic acid, which is a polyolefin. Ethylene oxide oil can also be used. Examples of natural oils include, but are not limited to, sulfonated oil, which is a glyceride of vegetable or animal origin, sulfuric acid ester, sulfitated oil, which is fish oil glyceride, an alkylsulfonic acid ester, and monoglyceride-based oil.

The ratio in the mixture of synthetic oil, natural oil and the mixture of components of synthetic oil and natural oil is determined at its sole discretion.

(4) The following post-retreatment processing step, which is part of the skin production method, is described below.

In the post-treatment step, after the retanning step, the skin is dried and finally finished (drying / coating). Before a wet finish, wet skin that has been dyed and healed is pre-dried to fix the grease and dye more firmly and to add coloring strength, water resistance and elasticity. Then the skin is leveled to stretch the lines on its surface. One of the characteristics of the method proposed here is the inclusion of such a stage of linear stretching.

Neutralized, retaned, dyed and healed skin contains approximately 70 to 80% water, so that the water is squeezed out to facilitate drying. To stretch the skin, use a pressure device and make it even to remove water. Thus, the water content is reduced to a range from 50 to 60%. After that, the skin is dried in a suspended state at a temperature of from 30 to 50 ° C to a water content of 7% or less. Such drying can be carried out by peeling and sticking the skin onto a glass sheet or by vacuum drying. Drying is followed by conditioning to add a little water to the dried skin, bringing the water content to a suitable level.

Then carry out a hard work to regulate the softness of the skin. For this purpose, a vibrational weight is used.

After gripping, felting is carried out for 3.5-6.5 hours to loosen the skin fibers and, as a result, soften the skin.

Then carry out drying on the grid, where the skin is attached to the grid using clamping devices and stretched. The skin is dried in this state for 2 to 3 hours at a temperature of 45 to 65 ° C. If such technological operations are carried out with precautions, conditioning, curing, felting and drying on a grid with pressure devices can be repeated.

This is followed by circumcision, in which the edges that have hardened as a result of drying are cut, pressure marks showing areas of pressure devices, and too thin areas to shape the skin. After that, felting is performed in the drum for 4-6 hours.

In the present invention, the aforementioned skin or skin obtained by chrome tanning of the aforementioned skin is used as a base, and form on the surface of such a base the coating film described in the present invention to provide a new natural skin with the desired tactile feel unique to it, not provided by ordinary genuine leathers.

The evenness (MIU / MMD) of genuine leather obtained by forming the coating film described in the present invention is not affected by the way the base is tanned, and even when a chromium tanning base is used, good evenness (MIU / MMD) can be achieved, almost same as in the case of applying the base tanned with glutaraldehyde.

However, the elasticity of the substrate affects the evenness (MIU / MMD) regardless of the tanning method, and if the substrate is rigid, good evenness (MIU / MMD) cannot be ensured. Probably, since when measuring MMD (the spread of the coefficient of surface friction), the soft base absorbs the fine surface irregularities of the coating film, and the MMD becomes small, thereby causing an increase in flatness (MIU / MMD), while the rigid base cannot absorb the thin surface roughness, and MMD increases, thereby causing a decrease in evenness (MIU / MMD).

Good evenness (MIU / MMD) can be achieved with a base with BLC (hardness / softness) of 3.0 or more.

What happens when a chrome tanning base is applied is described below.

Genuine leather is characterized in that the skin is obtained by tanning and retanning, which include:

(1) a pretreatment step before tanning the skin;

(2) a tanning step using a trivalent chromium complex as a tanning agent;

(3) a step in which the skin is retaned using a tanning agent based on a resin or synthetic tanning agent containing a polymer or a mixture of acrylic acid, methacrylic acid, an ester of acrylic acid or an ester of methacrylic acid, or a copolymer of any combination of the foregoing, where such a tanning agent is used in the amount of 10 weight percent based on the weight of the skin, after which the skin is dyed, and then subjected to fatliquoring using a lubricating agent; and

(4) a post-processing post-processing step.

Such a production method includes technological operations similar to those in the aforementioned method, and as described above, a resin-based retaner or synthetic tanning agent can be used.

(1) The tanning and retanning stages are described below.

(A) The tanning step is described below.

The front surface and the medial side obtained in the previous stage are anesthetized by neutralizing and removing the ash fluid used to soak the skin in the previous stage (spray water with a pH adjusted and carry out another process to accelerate the action of the proteolytic enzyme; the water used in this process has a temperature in the range from 30 to 35 ° C and contains sodium hydrosulfite containing from 1 to 2% ammonium chloride, etc.), and then the skin is softened in the presence of a proteolytic enzyme (apply soft itel mixed with pancreatin or another enzyme) (in this method, the skin is impregnated with water containing a suitable degrading enzyme using water containing from 0.8 to 1.2% of this enzyme preparation and 0.5% ammonium chloride), followed by collagen the fabric softens and the enzyme is removed.

Then the skin is soaked for approximately 3 hours in a solution, the pH of which is adjusted in the range from 2 to 3 with sulfuric acid and formic acid (pickling). This is necessary because the chrome tanning agent may not dissolve in a non-acid solution.

Then, a commercially available chromium sulfate tanning agent is added to the skin in an amount of 3.0 weight percent, after which sodium bicarbonate is gradually added to increase the basicity of the chrome tanning agent to allow the skin to absorb chromium. The temperature in the tanning bath is controlled in the range from 30 to 40 ° C, and the final pH at the end of the tanning is adjusted to 3.6. The tanning time is 5 hours. So that the chrome tanning agent penetrates the skin better, the pH is gradually increased. If the pH rises too quickly, chromium is adsorbed only on the surface of the skin.

The skin is washed in water and squeezed, and then its thickness is brought to the required level, after which the back side is scraped, further adjusting the thickness (scraping), at the same time defective parts are cut off on the periphery of the skin (circumcision).

Then the skin is treated with sodium formate, and the pH of the bath is adjusted in the range from 4.0 to 5.0 (neutralization step), and then the skin is retaned. The retanning is carried out at 35 ° C for 60 minutes using from 5 to 15 weight percent of a synthetic tanning agent (formaldehyde-containing product of condensation of naphthalenesulfonic acid or methylene-containing product of cyclopolycondensation of arylsulfonic acid) based on skin weight, as well as from 3 to 10 weight percent of tanning agent based on polyacrylic resin based on skin weight. The specified retanning agent can be used in a smaller amount than any glutaraldehyde tanning agent, partly because chrome tanning agent has a stronger tanning effect on the skin than glutaraldehyde, and partly because sufficient heat resistance was provided at the tanning stage. The main objective of the retanning step is to deposit a retanter between the skin fibers to increase bulkiness and other tactile properties and flexibility.

(B) The dyeing / fatliquoring step is described below.

From 0.5 to 5 weight percent of an acid azo dye is added based on the weight of the skin (depending on the desired color, a different dye should be used) and the skin is left in the dye solution for 2 hours, after which the pH of the solution is reduced to 4.0, using fixing the dye on the skin formic acid, while coloring the skin.

Then, from 3 to 12 weight percent based on the weight of the skin of the lubricating agent (mixed oil containing synthetic oil and natural oil) is added and the skin is left in the aforementioned fatliquoring solution for 1 hour, after which the pH of the solution is reduced to 3.5, using fixing the lubricating agent on the skin formic acid.

(2) Formation of a coating film

The coating film is formed in the same manner as proposed in the present invention.

The following describes the test and measurement methods used in the present invention.

To ensure the objectivity of the assessment, the present invention used the measuring method and means illustrated in Fig.13 and 14, which are explained below.

(1) Measurement of evenness (Fig.13)

Evenness is evaluated based on the conditions of surface friction.

(A) Measurement of average surface friction coefficient (MIU)

A load of 50 g is applied to the friction force sensor (13A shown in FIG. 13a, also called a “U-shaped sensor”, a U-shaped object 10 mm wide in the lower U-shaped part, where 20 string wires, each 0.5 mm are bundled with a total size of 10 mm and placed at the aforementioned 10 mm width) (KES-SE-SR-U friction roughness measuring device manufactured by Kato Tech), and in this state the friction force sensor moves at a constant speed 1 mm / s in the indicated direction (13F) for measuring surface friction μo (see fig.13c) until de friction force flow (13B, manual adjustment);

To calculate the surface friction μo, the friction force sensor 13A is mounted on the holder of the friction force sensor 13G of the friction force measuring system 13D and moves along the surface of the specimen 13E in the direction of travel (13F). The surface friction μo measured by the friction force sensor 13A is transmitted by the detector holder of the friction force sensor 13G to the friction force detection unit (13C), and then to the friction force measurement system (13D), where the detected force is converted to a value on the display the result is given. From the surface friction μo, the average surface friction coefficient μm (MIU) is calculated.

The average surface friction coefficient μm (MIU) is an indicator of surface slippage.

(B) Measurement of the average deviation of the coefficient of surface friction (MMD)

Similarly, the average deviation of the surface friction coefficient (also called the “friction coefficient spread” or MMD) is calculated from the surface friction μo. The average deviation of the coefficient of surface friction (MMD) is an indicator of surface roughness.

(C) Method for calculating evenness inherent in natural skin only

This indicator can be calculated by calculating the ratio (A) of the average surface friction coefficient and (ii) the average deviation of the surface friction coefficient (average deviation) (average surface friction coefficient (MIU) / average deviation of the coefficient of surface friction (MMD)).

(D) "Average surface friction coefficient (MIU) / average deviation of the coefficient of surface friction (MMD)" is used as an estimate of the evenness index. Its greater value corresponds to a better tactile sensation of the surface. For practical reasons, an acceptable range is 25 or more.

(2) Smoothness or its deficiency is determined by measuring the surface roughness and obtaining its average deviation (Fig. 14). 14 consists of 14a (enlarged image showing the device of the surface roughness sensor), 14b (drawing showing a system for measuring friction using a surface roughness sensor) and 14c (illustration of the average deviation of the SMD from the results of measuring the surface roughness using the surface roughness sensor )

(A) Calculation of SMD (Mean Surface Roughness Deviation)

SMD (Mean Surface Roughness Deviation) is calculated by measuring the surface roughness.

A surface roughness sensor (14A, also called a "U-shaped sensor") moves along the surface of a coating film formed on the surface of the resulting skin to measure vertical thickness spread and measure ultimately the surface roughness. The surface roughness sensor (14A) has a width of 5 mm in the lower U-shaped part, and a bundle of string wires, each 0.5 mm in size, is fixed at such a 5 mm width (KES-SE-SR-U instrument for measuring roughness during production friction Kato Tech). A load of 10 g (14A) is applied to the surface roughness sensor, and in this state, the surface roughness sensor moves at a constant speed of 1 mm / s in the indicated direction (14F) to measure the vertical thickness spread until the surface roughness detection is completed (14B, also called manual regulation), while obtaining SMD (average surface roughness deviation).

To calculate the surface roughness, the surface roughness sensor (14A) is installed on the system for measuring surface roughness (14D) and moves along the surface of the sample (14E) in the direction of movement (14F). The vertical thickness spread indicating the surface roughness measured with the friction force sensor (14A) is transmitted by the detector of the surface roughness sensor 13G to the surface roughness measurement system (14D), which calculates the average surface roughness deviation (SMD) and graphically represents (14c) its on the display.

(B) SMD (Mean Surface Roughness Deviation) is considered acceptable if its value is 2.5 μm or less.

(3) Whether or not the physical properties of the coating film are retained, such as wear resistance, are checked by measuring the following ratings:

(A) Wear resistance

The device for measuring wear resistance (Fig. 15) is described using the drawing, which shows a friction roller (width 60 mm, thickness 25 mm) (15a), as well as using the aforementioned device (Gakushin) to determine the assessment of the abrasion resistance of the material (15B ) on which such a friction roller is mounted (a general view is shown in FIG. 15b; AB301 manufactured by Tester Sangyo).

(B) The test method is described as follows:

Two test pieces, each 10 mm × 50 mm in size, are cut from the skin. One test piece should have a long side corresponding to the vertical direction of the skin (in the head-tail direction), while the other test piece should have a long side corresponding to the transverse direction (in the back-stomach direction). Each test piece (15C) is mounted on the friction roller (15A) of the friction measuring device, as shown in FIG. 15a, and the friction roller is connected to a lever under load (15E, 110 mm) and a load (15F), and then adjusted so that it is in contact with the test part of the device to determine the assessment of the resistance of the material to abrasion according to Gakushin (15B). Cut a piece of cotton canvas No. 6 (15D) with a width of 30 mm and a length of 250 mm. At this stage, the direction of weaving of the cotton canvas should be vertical with respect to the long side. Then a piece of cotton canvas is fixed on the test piece of the friction measuring device, so that its long side is parallel to the direction of movement of the test piece (the test piece is an arc with a radius of 200 mm and a width of 120 mm).

Then the mechanism is forced to work under a load of 1.0 kg (15F) at a speed of 30 cycles "back and forth" per minute at a distance of 100 mm, at the same time stopping it after every 500-1000 cycles "back and forth" to observe the state of the coverslip films with the naked eye, and friction is applied continuously until the coating film exfoliates.

The number of back-and-forth cycles is recorded, after which the coating film begins to peel off, and the measured number for the two pieces tested is averaged, thereby obtaining Gakushin wear resistance.

(4) Whether or not the strength of the coating film is maintained, is checked by measuring the dependence of strain on stress (that is, by obtaining a stress-strain curve) of the coating film formed on the surface of genuine leather. The measurement method should correspond to the method of measuring a dumbbell-shaped sample.

(A) Preparation of the test piece (FIG. 16)

The resin is poured into a silicone mold and left at room temperature (20 ± 5 ° C) for at least 3 days before drying to obtain a resin film with a thickness of about 0.4 to 0.8 mm.

Using a stamp for embossing, a dumbbell-like test piece is cut out of the obtained resin-based film (Fig. 16). In the center of the test piece, marks are applied at a distance of 30 mm between the points.

The width of the tested piece W (mm) - 20

The initial distance between the marks on the test piece L _o (mm) = 30

(B) Test Method

The thickness of the test piece is measured at three points C, L and R, as shown in FIG. 16, and the values measured at three points are averaged to obtain the thickness of the test piece T (mm).

Obtaining a load-tensile curve

To obtain a curve illustrating the relationship between the applied load and the stretch between the marks, a Tensilon tensile tester (AG-1 AUTO GRAPH manufactured by Shimadzu) is used, pulling the test piece at a speed of 100 ± 20 mm / min until it breaks.

Obtaining a stress-strain curve

(a) The load is divided by the cross-sectional area using the formula below to obtain the equivalent stress:

S = P / (W × T)

S: stress (MPa)

P: load (N)

W: width of test piece (mm)

T: test piece thickness (mm)

(b) To obtain equivalent deformation (degree of elongation) for stretching between the marks, the following formula is used:

s = ΔL / L _o × 100

s: strain (%)

ΔL: stretch between marks (mm)

L _o : initial distance between marks (mm)

(c) 10% module

Stress at 10% strain is defined as 10% modulus (unit: MPa).

Below the present invention is described using examples.

However, it should be noted that the present invention is not limited to the examples described below.

The examples described below are summarized as follows.

Example 1 is an example related to skin "having elasticity, softness, characterized by greater elasticity than is usually expected from the skin, not more extensibility than the usual level of skin extensibility, as well as the ability to restore" (Japan patent application No. 2007- 170359), where many specific examples of the production of a base are given as test examples. In this description, such test examples are collected with reference to Example 1 and are described in paragraphs 0081-0092.

Examples 2-10 are examples of the formation of a coating film on the surface of the substrate (BLC50) obtained in test 6 of the above example 1. Among them, examples 2-6 show specific examples of mixing soft and hard components to obtain a layer of a painted coating and medium and hard components to obtain a topcoat layer, when the formation of a colored coating layer and a topcoat layer of the coating film occurs on the surface of the substrate described in Example 1. On the other hand, Examples 7-10 represent th examples examine what happens when the blending ratio of soft and hard components constituting the colored coating layer is changed, while the mixing ratio of medium and hard components constituting the top coat layer, remains the same.

Example 11 is a specific example of how the formation of a coating film on the skin obtained by grinding the base (BLC50) obtained in example 1 can give favorable results.

Example 12 is a specific example of how the formation of a coating film on the surface of chrome tanned leather can give favorable results.

All results are summarized in table 4.

It should be recalled that the present invention is not at all limited to these examples.

Example 1

Example 1 is a specific example of the production of skin "having elasticity, softness, characterized by more significant elasticity than is usually expected from the skin, not more extensibility than the usual level of skin extensibility, as well as the ability to restore" (Japanese patent application No. 2007-170359 )

Genuine leather was obtained using sequential methods, including the stage of tanning the skin, as well as the stage of neutralization, retanning, dyeing and fatliquoring.

The skin was retaned using the tanning agent described below. All processing conditions, except tanning agent, were the same as the above conditions.

Each of the tanning agents used in the “retanning” step is listed below.

Table 1 Tanning agent Tanning agent
one Tanning agent
2 Tanning agent
3 Tanning agent
four Tanning agent of plant origin thirty 0 four 0 Synthetic
tanning agent Condensation Product of Aromatic Sulfonic Acid and Formaldehyde - 22 four 12 Methylene-containing cyclocondensation product of aromatic sulfonic acid and aromatic hydroxy compound - 0 8 10 Glyoxal 3 3 Total synthetic tannin 0 22 fifteen 25 Resin Polyacrylate Acrylic Acid Copolymer 0 0 12 12 Polycondensation product of melamine and formaldehyde 0 8 5 5 Total retanning agent thirty thirty 36 42 Metal Aluminum compound and aluminum compound 0 0 0 0

The lubricating agent used is listed below.

table 2 Component The applied amount (weight percent of the weight of scraped skin, taken as 100%) A mixture of oils containing synthetic oil and natural oil (mixed in a 1: 1 weight ratio) 17 weight%

The amount of lubricating agent used is a weight percent of the skin weight taken as 100 percent, and is determined based on practical experience in the implementation of the conventional stages of retanning, where the preferred range is from 15 to 19 percent by weight.

The tanning agents 1-4 mentioned above were used when aluminum was added separately to the tanning agent 4 to retan the skin, and the stiffness / softness and percentage of permanent deformation of the resulting skin were measured to test the effectiveness of each tanning agent and aluminum. The results are summarized for each skin obtained and the best results are presented.

The processing conditions for retanning, the degree of permanent deformation, and the BLC values are summarized below.

The BLC (stiffness / softness) indicator measures the depth to which the skin is pressed when a load of 500 g per unit area is pressed on the skin, indicating not only elasticity, but also the repulsive power of the skin. The unit of measurement for BLC is mm. The BLC value is an indicator of softness.

“Maximum percentage of permanent deformation” refers to the percentage of permanent deformation of the skin in the X-axis or in the Y-axis direction, whichever is greater, where the X-axis and Y-axis are defined as lines perpendicular to the sample. The percentage of permanent deformation is measured by applying an 8 kg load to stretch the sample and then removing the load to restore the original state of the sample, indicating the percentage by which the marked line is stretched, the percentage of permanent deformation is an indicator of the skin's ability to recover. These two measured values are used to determine the condition of the skin, and after the results of both measurements are in satisfactory agreement, the skin is considered acceptable.

The measured percentages of maximum residual deformation and BLC values were obtained in test 1 (used a retanning agent 1, consisting only of a tanning agent of plant origin (does not contain resin)), in test 2 (used a retanning agent 2, consisting only of a synthetic tanning agent (does not contain resin) test 3 (there is a tanning agent of plant origin, synthetic tanning agent and resin) and in test 4 (a combination of synthetic tanning agent with resin).

In test 1, the BLC value is low, equal to 3.67. The maximum percentage of permanent deformation is 7.6, which is not a problem, but the BLC value is too low. In the present invention, both the results of measuring the BLC value and the maximum percentage of permanent deformation should be in satisfactory ranges.

In test 2, the BLC value is low, equal to 4.22. The maximum percentage of permanent deformation is 10.6, which is not a problem, but the BLC value is too low. In the present invention, both the results of measuring the BLC value and the maximum percentage of permanent deformation should be in satisfactory ranges.

Tests 1 and 2 showed the results of the use of conventional retanders, such as tanning agents of plant origin and synthetic tanning agents, and, therefore, are considered as examples of the prototype.

Test 3 employs a retanner containing a tanning agent of plant origin, a synthetic tanning agent and a resin. Since the resin is contained in the retander, the BLC value in test 3 is higher than in test 1 or 2, and is specifically 4.47. However, the maximum percentage of permanent deformation is low, at 13.9. In the present invention, both the results of measuring the BLC value and the maximum percentage of permanent deformation should be in satisfactory ranges.

Test 4 (tanning agent 4), test 5 (tanning agent 4), test 8 (tanning agent 4), test 9 (tanning agent 4), test 10 (tanning agent 4) and test 11 (tanning agent 4) show the results of using a tanning agent consisting of synthetic tanning agent and resin. Compared to tests 1 and 3, such tests gave favorable results both in terms of the BLC value and the maximum percentage of permanent deformation.

In test 4, the BLC value was 4.78 and the maximum percentage of permanent deformation was 11.1; in test 5, the BLC value was 4.90 and the maximum percentage of permanent deformation was 11.5; in test 8, the BLC value was 4.70, and the maximum percentage of permanent deformation was 10.7; in test 9, the BLC value was 4.90 and the maximum percentage of permanent deformation was 12.0; in test 10, the BLC value was 4.72, and the maximum percentage of permanent deformation was 13.9; and in test 11, the BLC value was 4.42, and the maximum percentage of permanent deformation was 12.4.

On Fig summarized all the results, including the results of tests 6 and 7, where aluminum was added. If we compare the results of tests 4, 5, 8, 9, 10, and 11 with the results of test 3, based on the actual values obtained, we can conclude that the effects of the tanning agent consisting of a synthetic tanning agent and the resin of the present invention are obvious when the value BLC (hardness / softness) is 4.42 mm or more, but not more than 4.90 mm (indicated as B) and the maximum percentage of permanent deformation is 10.7 or more, but not more than 13.9 (indicated as A). (It should be noted that the combined use of tanning agent and resin was not widely known until the completion of the present invention, and only indicated an obvious illustration of the effects of the present invention. In this sense, the values indicated above as A and B are values entirely obtained using examples of the present invention.)

Test results are described below in which an aluminum compound was added and the skin was treated in the presence of aluminum.

The following are the maximum percentages of permanent deformation and BLC values in test 5 (No. 56), where 0 weight percent aluminum was used, in test 6 (No. 61), where 3 weight percent aluminum was used, and in test 7 (No. 82), where it was used 5 weight percent aluminum.

In Test 6 (No. 61), the maximum percentage of permanent deformation is 8.5 and the BLC value is 5.3, which corresponds to the target values of 10.0 or less (maximum percentage of permanent deformation) and 5.0 or more (BLC). When the maximum percent residual deformation and the BLC values measured in test 5 (No. 56), where the aluminum content was 0 weight percent (maximum percentage of permanent deformation = 11.5, BLC = 4.90), in test 7 (No. 82), where the aluminum content was 5 weight percent (maximum percentage of permanent deformation = 12.4, BLC = 4.77) and in the above test 6 (No. 61) were connected by curved lines, the graph in FIG. 17 was obtained. When examining the range of BLC values reaching the target value of 5.0 or more, and the range of maximum percent residual deformation reaching the target value of 10.0 or less, it became clear that the target value of BLC is achieved, provided that the aluminum content at the maximum percentage of residual deformation is from 0.7 to 4.0.

Based on the above results, it can be concluded that the maximum percentage of permanent deformation becomes 10.0 or less, and the BLC also reaches the target value of 5.0 or more, provided that the aluminum content is in the range from 0.7 to 4, 0.

Example 2

Examples 2-0 are examples of the formation of a coating film on the surface of a substrate (BLC50) obtained in Test 6 of the above Example 1. Among them, Examples 2-6 are specific examples of mixing soft and hard components for a painted coating layer and medium and hard components for the topcoat layer, when the formation of the colored coating layer and the top coating layer of the coating film occurs on the surface of the substrate described in Example 1. On the other hand, Examples 7-10 are examples of studying what happens when the blending ratio of soft and hard components constituting the colored coating layer is changed while the ratio -components in mixtures of medium and soft components forming the overcoat layer is the same.

(A) Example 2 below describes the steps for forming the coating film of the present invention on the basis of natural skin obtained in the above-mentioned test 6 of Example 1.

A coating film of a primer was formed on natural skin (coating consumption = 40 g / m ² , film thickness = 5 μm, after which a base coating layer was formed (coating consumption = 45 g / m ² , film thickness = 9 μm.

On top of the main coating layer, the next colored coating layer and a topcoat layer were formed.

The rigid component (resin, whose 10% modulus is greater than 2.3, but not more than 3.0) of the resin, containing a two-component polyurethane resin and polyurethane resin, which was used to form the colored coating layer, was contained in an amount from 48 to 90 weight percent, in which, in particular, uses a two-component aliphatic polyurethane, which is a matting agent (whose 10% module is 2.88; see figure 3) and another two-component aliphatic polyurethane (whose 10% module is 2.77; see figure 4 ) giving a total content of 70 weight%.

The soft component (resin, whose 10% modulus is greater than 0.0, but not more than 1.0) of the resin, containing a two-component polyurethane resin and polyurethane resin, which is used to form a coating layer, was contained in an amount of 52 to 10 weight percent, in which, in particular, uses a two-component aliphatic polyurethane (whose 10% modulus is 0.54; see Fig. 5) and another two-component aliphatic polyurethane (whose 10% modulus is 0.30; see Fig. 6), giving a total content of 30 weight% of the soft component.

The middle component (resin, whose 10% modulus is greater than 1.0, but not more than 2.3) of the resin containing a two-component polyurethane resin and polyurethane resin, which was used to form the aforementioned topcoat layer, was contained in an amount of from 15.0 to 35, 0 weight percent, in which, in particular, the weight content of the two-component aliphatic polyurethane resin (whose 10% modulus is 1.89; see FIG. 8) was 7.5% of the average component.

The soft component (resin, whose 10% modulus is greater than 0.0, but not more than 1.0) of a resin containing a two-component polyurethane resin and a polyurethane resin, which was used to form the aforementioned topcoat layer, was contained in an amount of from 85.0 to 65, 0 weight percent, in which, in particular, a two-component aliphatic polyurethane (matting resin) is used (whose 10% module is 0.67; see Fig. 9), another two-component aliphatic polyurethane resin (whose 10% module is 0.54; see figure 10) and a copolymer of acrylic polymer-urethane according Limera (whose 10% modulus is 0.11; see 11), giving a total content of 92.5 weight%.

(B) The following two points were evaluated. According to a preliminary measurement of genuine leathers using the KES-SE-SR-U friction roughness measuring instrument (manufactured by Kato Tech), the leathers were considered acceptable when their (a) smoothness (SMD) was 2.5 μm or less, and the evenness (MIU / MMD) was 25 or more, and (b) the result of the endurance test was 4000 cycles or more. Therefore, they came to the conclusion that skin problems, the solution of which is provided by the present invention, are solved when two evaluation criteria (a) and (b) are fulfilled.

(C) In Example 2 (a), the smoothness (SMD) was 0.86 μm and the evenness (MIU / MMD) was 34.3, while the aforementioned rating (b) was 5000 cycles, according to the evaluation of paragraph (B) confirming that both assessment criteria (a) and (b) have been met.

Example 3

(A) In Example 3, the steps of forming the coating film of the present invention were carried out on the basis of natural skin obtained in the above-mentioned Test 6 of Example 1.

A coating film of a primer was formed on natural skin (coating consumption = 40 g / m ² , film thickness = 5 μm), after which a layer of the main coating was formed (coating consumption = 45 g / m ² , film thickness = 9 μm).

On top of the main coating layer, the next colored coating layer and a topcoat layer were formed.

The rigid component (resin, whose 10% modulus is greater than 2.3, but not more than 3.0) of the resin, containing a two-component polyurethane resin and polyurethane resin, which was used to form the colored coating layer, was contained in an amount from 48 to 90 weight percent, in which, in particular, uses a two-component aliphatic polyurethane, which is a matting agent (whose 10% module is 2.88; see figure 3) and another two-component aliphatic polyurethane (whose 10% module is 2.77; see figure 4 ) giving a total content of 70 weight%.

The soft component (resin, whose 10% modulus is greater than 0.0, but not more than 1.0) of the resin containing a two-component polyurethane resin and polyurethane resin, which was used to form the colored coating layer, was contained in an amount of 52 to 10 weight percent, in which, in particular, uses a two-component aliphatic polyurethane (whose 10% modulus is 0.54; see Fig. 5) and another two-component aliphatic polyurethane (whose 10% modulus is 0.30; see Fig. 6), giving a total the content of the soft component is 30 weight%.

The middle component (resin, whose 10% modulus is greater than 1.0, but not more than 2.3) of the resin containing a two-component polyurethane resin and polyurethane resin, which was used to form the aforementioned topcoat layer, was contained in an amount of from 15.0 to 35, 0 weight percent, in which, in particular, the weight content of the two-component aliphatic polyurethane resin (whose 10% modulus is 1.89; see Fig. 8) was 15% based on the average component.

The soft component (resin, whose 10% modulus is greater than 0.0, but not more than 1.0) of a resin containing a two-component polyurethane resin and a polyurethane resin, which was used to form the aforementioned topcoat layer, was contained in an amount of from 85.0 to 65, 0 weight percent, in which, in particular, a two-component aliphatic polyurethane (matting resin) is used (whose 10% module is 0.67; see Fig. 9), another two-component aliphatic polyurethane resin (whose 10% module is 0.54; see figure 10) and 30 weight percent acrylic copolymer in Immer-urethane resin (whose 10% modulus is 0.11;. 11 cm), giving a sum content of 85% by weight.

(B) The following two points were evaluated. According to a preliminary measurement of genuine leathers using the KES-SE-SR-U friction roughness measuring instrument (manufactured by Kato Tech), the leathers were considered acceptable when their (a) smoothness (SMD) was 2.5 μm or less, and the evenness (MIU / MMD) was 25 or more, and (b) the result of the endurance test was 4000 cycles or more. Therefore, they came to the conclusion that skin problems, the solution of which is provided by the present invention, are solved when two evaluation criteria (a) and (b) are fulfilled.

(C) In Example 3 (a), the smoothness (SMD) was 0.89 μm and the evenness (MIU / MMD) was 30.1, while the aforementioned score (b) was 7500 cycles, as estimated according to ( B) confirming that both assessment criteria (a) and (b) have been met.

Example 4

(A) In Example 4, the steps of forming the coating film of the present invention were carried out on the basis of natural skin obtained in the above-mentioned Test 6 of Example 1.

A coating film of a primer was formed on natural skin (coating consumption = 40 g / m ² , film thickness = 5 μm), after which a layer of the main coating was formed (coating consumption = 45 g / m ² , film thickness = 9 μm).

On top of the main coating layer, the following, a colored coating layer and a top coating layer were formed.

The rigid component (resin, whose 10% modulus is greater than 2.3, but not more than 3.0) of the resin, containing a two-component polyurethane resin and polyurethane resin, which was used to form the colored coating layer, was contained in an amount from 48 to 90 weight percent, in which, in particular, uses a two-component aliphatic polyurethane, which is a matting agent (whose 10% module is 2.88; see figure 3), and another two-component aliphatic polyurethane (whose 10% module is 2.77; see. 4) giving a total content of 70 weight%.

The soft component (resin, whose 10% modulus is greater than 0.0, but not more than 1.0) of the resin containing a two-component polyurethane resin and polyurethane resin, which was used to form the colored coating layer, was contained in an amount of 52 to 10 weight percent, in which, in particular, uses a two-component aliphatic polyurethane (whose 10% modulus is 0.54; see Fig. 5) and another two-component aliphatic polyurethane (whose 10% modulus is 0.30; see Fig. 6), giving a total the content of the soft component is 30 weight%.

The middle component (resin, whose 10% modulus is greater than 1.0, but not more than 2.3) of the resin containing a two-component polyurethane resin and polyurethane resin, which was used to form the aforementioned topcoat layer, was contained in an amount of from 15.0 to 35, 0 weight percent, in which, in particular, the weight content of the two-component aliphatic polyurethane resin (whose 10% modulus is 1.89; see FIG. 8) was 25% based on the average component.

The soft component (resin, whose 10% modulus is greater than 0.0, but not more than 1.0) of a resin containing a two-component polyurethane resin and a polyurethane resin, which was used to form the aforementioned topcoat layer, was contained in an amount of from 85.0 to 65, 0 weight percent, in which, in particular, a two-component aliphatic polyurethane (matting resin) is used (whose 10% module is 0.67; see Fig. 9), another two-component aliphatic polyurethane resin (whose 10% module is 0.54; see figure 10) and a copolymer of acrylic polymer-urethane according Limera (whose 10% modulus is 0.11; see FIG. 11), giving a total content of 75 weight%.

(B) The following two points were evaluated. According to a preliminary measurement of genuine leathers using the KES-SE-SR-U friction roughness measuring instrument (manufactured by Kato Tech), the leathers were considered acceptable when their (a) smoothness (SMD) was 2.5 μm or less, and the evenness (MIU / MMD) was 25 or more, and (b) the result of the endurance test was 4000 cycles or more. Therefore, they came to the conclusion that skin problems, the solution of which is provided by the present invention, are solved when two evaluation criteria (a) and (b) are fulfilled.

(C) In Example 4 (a), the smoothness (SMD) was 0.74 μm and the evenness (MIU / MMD) was 30.4, while the aforementioned rating (b) was 9000 cycles, according to the evaluation of paragraph (B) confirming that both assessment criteria (a) and (b) have been met.

Example 5

(A) In Example 5, the steps of forming the coating film of the present invention were carried out on the basis of natural skin obtained in the above-mentioned test 6 of Example 1.

A coating film of a primer was formed on natural skin (coating consumption = 40 g / m ² , film thickness = 5 μm), after which a layer of the main coating was formed (coating consumption = 45 g / m ² , film thickness = 9 μm).

On top of the main coating layer, the next colored coating layer and a topcoat layer were formed.

The rigid component (resin, whose 10% modulus is greater than 2.3, but not more than 3.0) of the resin, containing a two-component polyurethane resin and polyurethane resin, which was used to form the colored coating layer, was contained in an amount from 48 to 90 weight percent, in which, in particular, uses a two-component aliphatic polyurethane, which is a matting agent (whose 10% module is 2.88; see figure 3), and another two-component aliphatic polyurethane (whose 10% module is 2.77; see. 4) giving a total content of 70 weight%.

The soft component (resin, whose 10% modulus is greater than 0.0, but not more than 1.0) of the resin containing a two-component polyurethane resin and polyurethane resin, which was used to form the colored coating layer, was contained in an amount of 52 to 10 weight percent, in which, in particular, uses a two-component aliphatic polyurethane (whose 10% modulus is 0.54; see Fig. 5) and another two-component aliphatic polyurethane (whose 10% modulus is 0.30; see Fig. 6), giving a total the content of the soft component is 30 weight%.

The middle component (resin, whose 10% modulus is greater than 1.0, but not more than 2.3) of the resin containing a two-component polyurethane resin and polyurethane resin, which was used to form the aforementioned topcoat layer, was contained in an amount of from 15.0 to 35, 0 weight percent, in which, in particular, the weight content of a two-component aliphatic polyurethane resin (whose 10% modulus is 1.89; see FIG. 8) was 30% based on the average component.

The soft component (resin, whose 10% modulus is greater than 0.0, but not more than 1.0) of a resin containing a two-component polyurethane resin and a polyurethane resin, which was used to form the aforementioned topcoat layer, was contained in an amount of from 85.0 to 65, 0 weight percent, in which, in particular, a two-component aliphatic polyurethane (matting resin) is used (whose 10% module is 0.67; see Fig. 9), another two-component aliphatic polyurethane resin (whose 10% module is 0.54; see figure 10) and a copolymer of acrylic polymer-urethane according Limera (whose 10% modulus is 0.11; see 11), giving a total content of 70 weight%.

(B) The following two points were evaluated. According to a preliminary measurement of genuine leathers using the KES-SE-SR-U friction roughness measuring instrument (manufactured by Kato Tech), the leathers were considered acceptable when their (a) smoothness (SMD) was 2.5 μm or less, and the evenness (MIU / MMD) was 25 or more and (b) the result of the endurance test was 4000 cycles or more. Therefore, they came to the conclusion that skin problems, the solution of which is provided by the present invention, are solved when two evaluation criteria (a) and (b) are fulfilled.

(C) In Example 5 (a), the smoothness (SMD) was 0.68 μm and the evenness (MIU / MMD) was 33.6, while the aforementioned score (b) was 7,500 cycles, as estimated according to ( B) confirming that both assessment criteria (a) and (b) have been met.

Example 6

(A) In Example 6, the steps of forming a coating film of the present invention were carried out on the basis of natural skin obtained in the above-mentioned Test 6 of Example 1.

A coating film of a primer was formed on natural skin (coating consumption = 40 g / m ² , film thickness = 5 μm), after which a layer of the main coating was formed (coating consumption = 45 g / m ² , film thickness = 9 μm).

On top of the main coating layer, the next colored coating layer and a topcoat layer were formed.

The rigid component (resin, whose 10% modulus is greater than 2.3, but not more than 3.0) of the resin, containing a two-component polyurethane resin and polyurethane resin, which was used to form the colored coating layer, was contained in an amount from 48 to 90 weight percent, in which, in particular, uses a two-component aliphatic polyurethane, which is a matting agent (whose 10% module is 2.88; see figure 3), and another two-component aliphatic polyurethane (whose 10% module is 2.77; see. 4) giving a total content of 70 weight%.

The soft component (resin, whose 10% modulus is greater than 0.0, but not more than 1.0) of the resin containing a two-component polyurethane resin and polyurethane resin, which was used to form the colored coating layer, was contained in an amount of 52 to 10 weight percent, in which, in particular, uses a two-component aliphatic polyurethane (whose 10% modulus is 0.54; see Fig. 5) and another two-component aliphatic polyurethane (whose 10% modulus is 0.30; see Fig. 6), giving a total the content of the soft component is 30 weight%.

The middle component (resin, whose 10% modulus is greater than 1.0, but not more than 2.3) of the resin containing a two-component polyurethane resin and polyurethane resin, which was used to form the aforementioned topcoat layer, was contained in an amount of from 15.0 to 35, 0 weight percent, in which, in particular, a two-component aliphatic polyurethane resin (whose 10% modulus is 1.89; see FIG. 8) is used at 37.5 weight percent based on the middle component.

The soft component (resin, whose 10% modulus is greater than 0.0, but not more than 1.0) of a resin containing a two-component polyurethane resin and a polyurethane resin, which was used to form the aforementioned topcoat layer, was contained in an amount of from 85.0 to 65, 0 weight percent, in which, in particular, a two-component aliphatic polyurethane (matting resin) is used (whose 10% module is 0.67; see Fig. 9), another two-component aliphatic polyurethane resin (whose 10% module is 0.54; see figure 10) and a copolymer of acrylic polymer-urethane according Limera (whose 10% modulus is 0.11; see 11), giving a total content of 62.5 weight%.

(B) The following two points were evaluated. According to a preliminary measurement of genuine leathers using the KES-SE-SR-U friction roughness measuring instrument (manufactured by Kato Tech), the leathers were considered acceptable when their (a) smoothness (SMD) was 2.5 μm or less, and the evenness (MIU / MMD) was 25 or more, and (b) the result of the endurance test was 4000 cycles or more. Therefore, we came to the conclusion that skin problems, the solution of which is provided by the present invention, are solved when two evaluation criteria (a) and (b) are fulfilled.

(C) In Example 6 (a), the smoothness (SMD) was 0.72 μm and the evenness (MIU / MMD) was 32.9, while the aforementioned rating (b) was 5500 cycles, according to the evaluation of paragraph (B) confirming that both assessment criteria (a) and (b) were fulfilled.

Example 7

(A) Examples 7-10 are examples of the study of what happens when the ratio of components in mixtures of soft and hard components forming a colored layer of a coating film changes, while the ratio of components in mixtures of medium and soft components forming a top layer of a coating the film remains the same.

A coating film of a primer was formed on natural skin (coating consumption = 40 g / m ² , film thickness = 5 μm, after which a base coating layer was formed (coating consumption = 45 g / m ² , film thickness = 9 μm.

On top of the main coating layer, the next colored coating layer and a topcoat layer were formed.

The rigid component (resin, whose 10% modulus is greater than 2.3, but not more than 3.0) of the resin, containing a two-component polyurethane resin and polyurethane resin, which was used to form the colored coating layer, was contained in an amount from 48 to 90 weight percent, in which, in particular, uses a two-component aliphatic polyurethane, which is a matting agent (whose 10% module is 2.88; see figure 3), and another two-component aliphatic polyurethane (whose 10% module is 2.77; see. 4) giving a total content of 90 weight%.

The soft component (resin, whose 10% modulus is greater than 0.0, but not more than 1.0) of the resin containing a two-component polyurethane resin and polyurethane resin, which was used to form the colored coating layer, was contained in an amount of 52 to 10 weight percent, in which, in particular, uses a two-component aliphatic polyurethane (whose 10% modulus is 0.54; see Fig. 5) and another two-component aliphatic polyurethane (whose 10% modulus is 0.30; see Fig. 6), giving a total the content of the soft component is 10 weight%.

The middle component (resin, whose 10% modulus is greater than 1.0, but not more than 2.3) of the resin containing a two-component polyurethane resin and polyurethane resin, which was used to form the aforementioned topcoat layer, was contained in an amount of from 15.0 to 35, 0 weight percent, in which, in particular, the weight content of the two-component aliphatic polyurethane resin (whose 10% modulus is 1.89; see FIG. 8) was 25% based on the average component.

The soft component (resin, whose 10% modulus is greater than 0.0, but not more than 1.0) of a resin containing a two-component polyurethane resin and a polyurethane resin, which was used to form the aforementioned topcoat layer, was contained in an amount of from 85.0 to 65, 0 weight percent, in which, in particular, a two-component aliphatic polyurethane (matting resin) is used (whose 10% module is 0.67; see Fig. 9), another two-component aliphatic polyurethane resin (whose 10% module is 0.54; see figure 10) and a copolymer of acrylic polymer-urethane according Limera (whose 10% modulus is 0.11; see FIG. 11), giving a total content of 75 weight%.

(B) The following two points were evaluated. According to a preliminary measurement of genuine leathers using the KES-SE-SR-U friction roughness measuring instrument (manufactured by Kato Tech), the leathers were considered acceptable when their (a) smoothness (SMD) was 2.5 μm or less, and the evenness (MIU / MMD) was 25 or more, and (b) the result of the endurance test was 4000 cycles or more. Therefore, they came to the conclusion that skin problems, the solution of which is provided by the present invention, are solved when two evaluation criteria (a) and (b) are fulfilled.

(C) In Example 7 (a), the smoothness (SMD) was 0.59 μm and the evenness (MIU / MMD) was 32.7, while the aforementioned estimate (b) was 10,000 cycles, according to the estimate of paragraph (B) confirming that both assessment criteria (a) and (b) have been met.

Example 8

Example 8 is an example of a study of what happens when the ratio of components in mixtures of soft and hard components forming a colored layer of a coating film changes, while the ratio of components in mixtures of medium and hard components forming a top layer of a coating film remains the same.

(A) In Example 8, the steps of forming a coating film of the present invention were carried out on the basis of natural skin obtained in the above-mentioned Test 6 of Example 1.

A coating film of a primer was formed on natural skin (coating consumption = 40 g / m ² , film thickness = 5 μm, after which a base coating layer was formed (coating consumption = 45 g / m ² , film thickness = 9 μm.

On top of the main coating layer, the next colored coating layer and a topcoat layer were formed.

The rigid component (resin, whose 10% modulus is greater than 2.3, but not more than 3.0) of the resin, containing a two-component polyurethane resin and polyurethane resin, which was used to form the colored coating layer, was contained in an amount from 48 to 90 weight percent, in which, in particular, uses a two-component aliphatic polyurethane, which is a matting agent (whose 10% module is 2.88; see figure 3), and another two-component aliphatic polyurethane (whose 10% module is 2.77; see. 4), giving a total content of 80 weight%.

The soft component (resin, whose 10% modulus is greater than 0.0, but not more than 1.0) of the resin containing a two-component polyurethane resin and polyurethane resin, which was used to form the colored coating layer, was contained in an amount of 52 to 10 weight percent, in which, in particular, uses a two-component aliphatic polyurethane (whose 10% modulus is 0.54; see Fig. 5) and another two-component aliphatic polyurethane (whose 10% modulus is 0.30; see Fig. 6), giving a total the content of the soft component is 20 weight%.

The middle component (resin, whose 10% modulus is greater than 1.0, but not more than 2.3) of the resin containing a two-component polyurethane resin and polyurethane resin, which was used to form the aforementioned topcoat layer, was contained in an amount of from 15.0 to 35, 0 weight percent, in which, in particular, the weight content of the two-component aliphatic polyurethane resin (whose 10% modulus is 1.89; see FIG. 8) was 25% based on the average component.

The soft component (resin, whose 10% modulus is greater than 0.0, but not more than 1.0) of a resin containing a two-component polyurethane resin and a polyurethane resin, which was used to form the aforementioned topcoat layer, was contained in an amount of from 85.0 to 65, 0 weight percent, in which, in particular, a two-component aliphatic polyurethane (matting resin) is used (whose 10% module is 0.67; see Fig. 9), another two-component aliphatic polyurethane resin (whose 10% module is 0.54; see figure 10) and a copolymer of acrylic polymer-urethane according Limera (whose 10% modulus is 0.11; see FIG. 11) [[%]], giving a total content of 75% by weight.

(B) The following two points were evaluated. According to a preliminary measurement of genuine leathers using the KES-SE-SR-U friction roughness measuring instrument (manufactured by Kato Tech), the leathers were considered acceptable when their (a) smoothness (SMD) was 2.5 μm or less, and the evenness (MIU / MMD) was 25 or more, and (b) the result of the endurance test was 4000 cycles or more. Therefore, they came to the conclusion that skin problems, the solution of which is provided by the present invention, are solved when two evaluation criteria (a) and (b) are fulfilled.

(C) In Example 8 (a), the smoothness (SMD) was 1.02 μm and the evenness (MIU / MMD) was 30.6, while the aforementioned score (b) was 8500 cycles, as estimated according to ( B) confirming that both assessment criteria (a) and (b) have been met.

Example 9

Example 9 is an example of a study of what happens when the ratio of components in mixtures of soft and hard components forming a colored layer of a coating film changed, while the ratio of components in mixtures of medium and hard components forming a top layer of a coating film .

(A) In Example 9, the steps of forming the coating film of the present invention were carried out on the basis of natural skin obtained in the above-mentioned Test 6 of Example 1.

A coating film of a primer was formed on natural skin (coating consumption = 40 g / m ² , film thickness = 5 μm, after which a base coating layer was formed (coating consumption = 45 g / m ² , film thickness = 9 μm.

On top of the main coating layer, the next colored coating layer and a topcoat layer were formed.

The rigid component (resin, whose 10% modulus is greater than 2.3, but not more than 3.0) of the resin, containing a two-component polyurethane resin and polyurethane resin, which was used to form the colored coating layer, was contained in an amount from 48 to 90 weight percent, in which, in particular, uses a two-component aliphatic polyurethane, which is a matting agent (whose 10% module is 2.88; see figure 3), and another two-component aliphatic polyurethane (whose 10% module is 2.77; see. 4), giving a total content of 60 weight%.

The soft component (resin, whose 10% modulus is greater than 0.0, but not more than 1.0) of the resin containing a two-component polyurethane resin and polyurethane resin, which was used to form the colored coating layer, was contained in an amount of 52 to 10 weight percent, in which, in particular, uses a two-component aliphatic polyurethane (whose 10% modulus is 0.54; see Fig. 5) and another two-component aliphatic polyurethane (whose 10% modulus is 0.30; see Fig. 6), giving a total the content of the soft component is 40 weight%.

The middle component (resin, whose 10% modulus is greater than 1.0, but not more than 2.3) of the resin containing a two-component polyurethane resin and polyurethane resin, which was used to form the aforementioned topcoat layer, was contained in an amount of from 15.0 to 35, 0 weight percent, in which, in particular, the weight content of a two-component aliphatic polyurethane resin (whose 10% modulus is 1.89; see FIG. 8) was 25% based on the average component.

The soft component (resin, whose 10% modulus is greater than 0.0, but not more than 1.0) of the resin containing a two-component polyurethane resin and polyurethane resin, which was used to form the aforementioned topcoat layer, was contained in an amount of from 85.0 to 65, 0 weight percent, in which, in particular, a two-component aliphatic polyurethane (matting resin) is used (whose 10% module is 0.67; see Fig. 9), another two-component aliphatic polyurethane resin (whose 10% module is 0.54; see figure 10) and a copolymer of acrylic polymer-urethane p olimer (whose 10% modulus is 0.11; see FIG. 11), giving a total content of 75 weight%.

(B) The following two points were evaluated. According to a preliminary measurement of genuine leathers using the KES-SE-SR-U friction roughness measuring instrument (manufactured by Kato Tech), the leathers were considered acceptable when their (a) smoothness (SMD) was 2.5 μm or less, and the evenness (MIU / MMD) was 25 or more, and (b) the result of the endurance test was 4000 cycles or more. Therefore, they came to the conclusion that skin problems, the solution of which is provided by the present invention, are solved when two evaluation criteria (a) and (b) are fulfilled.

(C) In Example 9, (a) the smoothness (SMD) was 0.70 μm and the evenness (MIU / MMD) was 34.1, while the aforementioned estimate (b) was 5000 cycles, according to the estimate of paragraph (B) confirming that both assessment criteria (a) and (b) have been met.

Example 10

Example 10 is an example of a study of what happens when the ratio of components in mixtures of soft and hard components forming a colored layer of a coating film changes, while the ratio of components in mixtures of medium and hard components forming a top layer of a coating film remains the same .

(A) In Example 10, the steps of forming a coating film of the present invention were carried out on the basis of natural skin obtained in the above-mentioned Test 6 of Example 1.

A coating film of a primer was formed on natural skin (coating consumption = 40 g / m ² , film thickness = 5 μm), after which a layer of the main coating was formed (coating consumption = 45 g / m ² , film thickness = 9 μm).

On top of the main coating layer, the next colored coating layer and a topcoat layer were formed.

The rigid component (resin, whose 10% modulus is greater than 2.3, but not more than 3.0) of the resin, containing a two-component polyurethane resin and polyurethane resin, which was used to form the colored coating layer, was contained in an amount from 48 to 90 weight percent, in which, in particular, uses a two-component aliphatic polyurethane, which is a matting agent (whose 10% module is 2.88; see figure 3), and another two-component aliphatic polyurethane (whose 10% module is 2.77; see. 4) giving a total content of 50 weight%.

The soft component (resin, whose 10% modulus is greater than 0.0, but not more than 1.0) of the resin containing a two-component polyurethane resin and polyurethane resin, which was used to form the colored coating layer, was contained in an amount of 52 to 10 weight percent, in which, in particular, uses a two-component aliphatic polyurethane (whose 10% modulus is 0.54; see Fig. 5) and another two-component aliphatic polyurethane (whose 10% modulus is 0.30; see Fig. 6), giving a total the content of the soft component is 50 weight%.

The middle component (resin, whose 10% modulus is greater than 1.0, but not more than 2.3) of the resin containing a two-component polyurethane resin and polyurethane resin, which was used to form the aforementioned topcoat layer, was contained in an amount of from 15.0 to 35, 0 weight percent, in which, in particular, the weight content of a two-component aliphatic polyurethane resin (whose 10% module was 1.89; see FIG. 8) was 25% based on the average component.

The soft component (resin, whose 10% modulus is greater than 0.0, but not more than 1.0) of a resin containing a two-component polyurethane resin and a polyurethane resin, which was used to form the aforementioned topcoat layer, was contained in an amount of from 85.0 to 65, 0 weight percent, in which, in particular, 25 weight percent of a two-component aliphatic polyurethane (matting resin) (whose 10% modulus is 0.67; see Fig. 9), 25 weight percent of another two-component aliphatic polyurethane resin (whose 10% the module was 0.54; see figure 10) and a copolymer of an acrylic polymer-urethane polymer (whose 10% modulus is 0.11; see FIG. 11), giving a total content of 75 weight%.

(B) The following two points were evaluated. According to a preliminary measurement of genuine leathers using the KES-SE-SR-U friction roughness measuring instrument (manufactured by Kato Tech), the leathers were considered acceptable when their (a) smoothness (SMD) was 2.5 μm or less, and the evenness (MIU / MMD) was 25 or more, and (b) the result of the endurance test was 4000 cycles or more. Therefore, they came to the conclusion that skin problems, the solution of which is provided by the present invention, are solved when two evaluation criteria (a) and (b) are fulfilled.

(C) In Example 10 (a), the smoothness (SMD) was 0.72 μm and the evenness (MIU / MMD) was 30.5, while the aforementioned rating (b) was 8500 cycles, as estimated by paragraph (B) confirming that both assessment criteria (a) and (b) have been met.

Example 11

Example 11 is a specific example of how the formation of a coating film on the skin obtained by grinding the base (BLC50) obtained in test 6 of example 1, could give positive results.

(A) The grinding step is described below and showing how the formation of a coating film on a polished surface could give positive results.

(1) Preparation of the base

The basis was obtained as follows.

To create a base, the aforementioned genuine leather was ground (using sanding paper) and scraped (such a base was used as a standard in the present invention).

(2) Formation of a coating film

A colored coating layer was formed by mixing 78 weight percent of the hard component (resin, whose 10% modulus is more than 2.3, but not more than 3.0) of a resin containing a two-component polyurethane resin and polyurethane resin, with 22 weight percent of the soft component (resin, whose 10% modulus is greater than 0.0, but not more than 1.0) of a resin containing a two-component polyurethane resin and polyurethane resin, while the aforementioned topcoat layer was formed by mixing 25.0 weight percent of the middle component (resin, whose 10% modulus bo less than 1.0, but not more than 2.3) resin containing a two-component polyurethane resin and polyurethane resin, with 75.0 weight percent of the soft component (resin, whose 10% modulus is more than 0.0, but not more than 1.0) resin containing a two-component polyurethane resin and a polyurethane resin.

(B) The following two points were evaluated. According to a preliminary measurement of genuine leathers using the KES-SE-SR-U friction roughness measuring instrument (manufactured by Kato Tech), the leathers were considered acceptable when their (a) smoothness (SMD) was 2.5 μm or less, and the evenness (MIU / MMD) was 25 or more, and (b) the result of the endurance test was 4000 cycles or more. Therefore, it was concluded that skin problems, the solution of which is provided by the present invention, are solved when two evaluation criteria (a) and (b) are fulfilled.

(C) In Example 11 (a), the smoothness (SMD) was 2.50 μm and the evenness (MIU / MMD) was 26.3, while the aforementioned estimate (b) was 10,000 cycles, according to the estimate of paragraph (B) confirming that both assessment criteria (a) and (b) have been met.

Example 12

Example 12 is a specific example of how the formation of a coating film on the surface of chrome tanned leather could give positive results.

(A) It was shown that positive results could be achieved by applying a coating film to the base (BLC50) obtained above in Example 1, according to the present invention, and to a base representing the skin obtained by grinding such a base (Example 11).

The following describes how you can still provide positive results without using such a framework, and that the coating film can be formed on such a different basis.

Foundation formation is described below.

Chrome tanning was carried out here. A trivalent chromium complex was used as a tanning agent at the tanning stage.

(1) Preparation of the base

The basis of genuine leather was obtained by pre-treatment before tanning, the tanning stage of the skin and the stages of neutralization, retanning, dyeing and fatliquoring.

Preliminary processing

Pretreatment before tanning is described below.

The skin taken from the skin of an adult cattle is soaked in water, then washed with water and removed, after which sticky substances (such as fat and meshes) are mechanically removed from the inside and the resulting skin is poured into an ash liquid to dissolve hair on the skin surface , then dirt is removed from the surface of the skin and the skin is impregnated with fly ash to loosen the fibers, after which the skin is divided into the front part (front side of the skin) and the mesure part (reverse side of the skin) with a tape knife. At this stage, keratin was removed from the epidermal layer and elastin from the lower layer. The resulting skin is in a state where all parts that are not collagen fibers are removed from its structure. Such traditional methods and means of processing, which are already widely known, can be chosen at your own discretion.

(B) Stage tanning

The front surface and the medial side obtained in the previous stage are anesthetized by neutralizing and removing the ash fluid used to soak the skin in the previous stage (spray water with a pH adjusted and carry out another process to accelerate the action of the proteolytic enzyme; the water used in this process has a temperature in the range from 30 to 35 ° C and contains sodium hydrosulfite containing from 1 to 2% ammonium chloride, etc.), and then the skin is softened in the presence of a proteolytic enzyme (apply soft itel mixed with pancreatin or another enzyme) (in this method, the skin is impregnated with water containing a suitable degrading enzyme using water containing from 0.8 to 1.2% of this enzyme preparation and 0.5% ammonium chloride), followed by collagen the fabric softens and the enzyme is removed.

Then the skin is soaked for approximately 3 hours in a solution, the pH of which is adjusted in the range from 2 to 3 with sulfuric acid and formic acid (pickling). This is necessary because the chrome tanning agent may not dissolve in a non-acid solution. Then, a commercially available chromium sulfate tanning agent is added to the skin in an amount of 3.0 weight percent, after which sodium bicarbonate is gradually added to increase the basicity of the chrome tanning agent to allow the skin to absorb chromium. The temperature in the tanning bath is controlled in the range from 30 to 40 ° C, and the final pH at the end of the tanning is adjusted to 3.6. The tanning time is 5 hours. So that the chrome tanning agent penetrates the skin better, the pH is gradually increased. If the pH rises too quickly, chromium is adsorbed only on the surface of the skin.

The skin is washed in water and squeezed, and then its thickness is brought to the required level, after which the back side is scraped, further adjusting the thickness (scraping), at the same time defective parts are cut off on the periphery of the skin (circumcision).

Then the skin is treated with sodium formate, and the pH of the bath is adjusted in the range from 4.0 to 5.0 (neutralization step), and then the skin is retaned. The retanning is carried out at 35 ° C for 60 minutes using from 5 to 15 weight percent of a synthetic tanning agent (formaldehyde-containing product of condensation of naphthalenesulfonic acid or methylene-containing product of cyclopolycondensation of arylsulfonic acid) based on skin weight, as well as from 3 to 10 weight percent of tanning agent based on polyacrylic resin based on skin weight. The specified retanning agent can be used in a smaller amount than any glutaraldehyde tanning agent, partly because chrome tanning agent has a stronger tanning effect on the skin than glutaraldehyde, and partly because sufficient heat resistance was provided at the tanning stage. The main objective of the retanning step is to deposit a retanter between the skin fibers to increase bulkiness and other tactile properties and flexibility.

(C) The dyeing / fatliquoring step is described below.

From 0.5 to 5 weight percent of an acid azo dye is added based on the weight of the skin (depending on the desired color, a different dye should be used) and the skin is left in the dye solution for 2 hours, after which the pH of the solution is reduced to 4.0, using fixing the dye on the skin formic acid, and thereby coloring the skin.

Then add from 3 to 12 weight percent, based on the weight of the skin, a lubricating agent (mixed oil containing synthetic oil and natural oil) and leave the skin in the aforementioned fatliquoring solution for 1 hour, after which the pH of the solution is reduced to 3.5, using formic acid to fix the lubricating agent to the skin.

(D) The following post-retreatment processing step, which is part of the skin production method, is described below.

In the post-treatment step, after the retanning step, the skin is dried and finally finished (drying / coating). Before a wet finish, wet skin that has been dyed and healed is pre-dried to fix the grease and dye more firmly and to add coloring strength, water resistance and elasticity. Then the skin is leveled to stretch the lines on its surface. One of the characteristics of the method proposed here is the inclusion of such a stage of linear stretching.

Neutralized, retaned, dyed and healed skin contains approximately 70 to 80% water, so that the water is squeezed out to facilitate drying. To stretch the skin, use a pressure device and make it even to remove water. Thus, the water content is reduced to a range from 50 to 60%. After that, the skin is dried in a suspended state at a temperature of from 30 to 50 ° C to a water content of 7% or less. Such drying can be carried out by peeling and sticking the skin onto a glass sheet or by vacuum drying. Drying is followed by conditioning to add a little water to the dried skin, bringing the water content to a suitable level.

Then carry out a hard work to regulate the softness of the skin. For this purpose, a vibrational weight is used.

After the gravy, felting is carried out for 3.5-6.5 hours in the drum to loosen the skin fibers and thereby soften the skin.

Then carry out drying on the grid, where the skin is attached to the grid using clamping devices and stretched. The skin is dried in this state for 2 to 3 hours at a temperature of 45 to 65 ° C. If such technological operations are carried out with precautions, conditioning, curing, felting and drying on a grid with pressure devices can be repeated.

This is followed by circumcision, in which the edges that have hardened as a result of drying are cut, pressure marks showing areas of pressure devices, and too thin areas to shape the skin. After that, felting is performed in the drum for 4-6 hours.

When the BLC hardness / softness of the chrome tanned leather obtained as described above was measured, it was 3.2 mm.

(2) The formation of a coating film is described below.

On the basis of a coating film was formed from the primer (coating consumption = 40 g / m ² , film thickness = 5 μm), after which a layer of the main coating was formed (coating consumption = 45 g / m ² , film thickness = 9 μm).

On top of the above-described layer, the next colored coating layer and a topcoat layer were formed.

(A) A colored coating layer was formed by mixing 78 weight percent of the hard component (resin, whose 10% modulus is more than 2.3, but not more than 3.0) of a resin containing a two-component polyurethane resin and polyurethane resin, with 22 weight percent of the soft component ( a resin whose 10% modulus is greater than 0.0, but not more than 1.0) a resin containing a two-component polyurethane resin and a polyurethane resin, while the aforementioned topcoat layer is formed by mixing 25.0 weight percent of the middle component (resin whose 10% module more than 1.0, but not more than 2.3) resin containing a two-component polyurethane resin and polyurethane resin, with 75.0 weight percent of the soft component (resin, whose 10% modulus is greater than 0.0, but not more than 1.0), the resin containing two-component polyurethane resin and polyurethane resin.

(B) The following two points were evaluated. According to a preliminary measurement of genuine leathers using the KES-SE-SR-U friction roughness measuring instrument (manufactured by Kato Tech), the leathers were considered acceptable when their (a) smoothness (SMD) was 2.5 μm or less, and the evenness (MIU / MMD) was 25 or more, and (b) the result of the endurance test was 4000 cycles or more. Therefore, they came to the conclusion that skin problems, the solution of which is provided by the present invention, are solved when two evaluation criteria (a) and (b) are fulfilled.

(C) In Example 12 (a), the smoothness (SMD) was 1.53 μm and the evenness (MIU / MMD) was 26.3, while the aforementioned score (b) was 10,000 cycles, as estimated by paragraph (B) confirming that both assessment criteria (a) and (b) have been met.

Example for comparison 6

In comparison example 6, the chromium-tanned leather described above in example 12 was used as the basis. In example 12, the coating film formed according to the present invention was evaluated.

(A) The comparison example 6 given here is an example showing that if the coating film is formed in a manner not strictly corresponding to the components and compositions specified in the present invention (such as when the topcoat layer is formed using only one rigid component without using an average component, with the specified hard component mixed with the soft component), the evaluation criteria are not met, in contrast to the above example 12.

Foundation preparation

The skin was obtained using chrome tanning according to the method specified in example 12.

The formation of a coating film is described below.

A coating film of a primer was formed on natural chrome tanned leather (coating consumption = 40 g / m ² , film thickness = 5 μm), after which a layer of the main coating was formed (coating consumption = 45 g / m ² , film thickness = 9 μm )

Layer formation

On top of the above-described layer, the next colored coating layer and a topcoat layer were formed.

The rigid component (resin, whose 10% modulus is greater than 2.3, but not more than 3.0) of the resin, containing a two-component polyurethane resin and polyurethane resin, which was used to form the colored coating layer, was contained in an amount from 48 to 90 weight percent, in which, in particular, applies 25 weight percent of a two-component aliphatic polyurethane, which is a matting agent (whose 10% module is 2.88; see FIG. 3), and 53 weight percent of another two-component aliphatic polyurethane (whose 10% module is 2, 77; see FIG. 4), d constituent content in the amount of 78% by weight.

The soft component (resin, whose 10% modulus is greater than 0.0, but not more than 1.0) of the resin containing a two-component polyurethane resin and polyurethane resin, which was used to form the colored coating layer, was contained in an amount of 52 to 10 weight percent, in which, in particular, applies 22 weight percent of a two-component aliphatic polyurethane (whose 10% modulus is 0.30; see FIG. 6), giving a total of 22 weight% of the soft component. The composition of the colored coating layer was within the composition of the coating film specified in the present invention.

The middle component (resin, whose 10% modulus is greater than 1.0, but not more than 2.3) of the resin containing the two-component polyurethane resin and polyurethane resin, which is used to form the aforementioned topcoat layer, was absent, while the hard component was contained in the amount of 27 weight percent (which is comparable with the content of the average component from 15.0 to 35.0 weight percent according to the present invention, which was one of the differences), and a soft component (resin, whose 10% modulus is more than 0.0, but not more than 1,0) resins containing bicomponent polyurethane resin and polyurethane resin, which was used to form the topcoat layer, contained 73 weight percent of an acrylic polymer-urethane polymer copolymer (whose 10% modulus is 0.11; see FIG. 11), giving a total content of 73 weight% in calculated on the soft component (although the middle component was not contained, but contained a hard component that was different from the composition of the coating film of the present invention).

(B) The following two points were evaluated. According to a preliminary measurement of genuine leathers using the KES-SE-SR-U friction roughness measuring instrument (manufactured by Kato Tech), the leathers were considered acceptable when their (a) smoothness (SMD) was 2.5 μm or less, and the evenness (MIU / MMD) was 25 or more, and (b) the result of the endurance test was 4000 cycles or more. Therefore, they came to the conclusion that skin problems, the solution of which is provided by the present invention, are solved when two evaluation criteria (a) and (b) are fulfilled.

(C) In the comparison example 6 (a), the smoothness (SMD) was 2.30 μm and the evenness (MIU / MMD) was 19.0, while the aforementioned score (b) was 20,000 cycles, as estimated by paragraph (B). Smoothness (SMD) and evenness (MIU / MMD) values were outside of the evaluation criterion (a).

Example for comparison 1

(A) In comparison example 1, the results of the formation of a coating film, the components of which are outside the conditions for forming the coating film of the present invention, on the basis of the skin obtained by grinding the skin, in turn, obtained in the usual tanning process, including glutaraldehyde as in Example 11. More specifically, the hard component was adapted to form a topcoat, or, more specifically, hard and soft were mixed to form a topcoat Components. In this case, positive results cannot be obtained.

(1) The resulting base was skin obtained by grinding the skin, in turn, obtained by the usual tanning process, including glutaraldehyde, as in example 11.

(2) The formation of a layer of a coating film is described below.

(A) A primer coating film was formed on natural skin (amount of applied coating = 40 g / m ² , film thickness = 5 μm, after which a basic coating was formed (amount of applied coating = 45 g / m ² , film thickness = 9 μm) .

(B) On top of the aforementioned layer, a next colored coating layer and a top coating layer were formed.

The rigid component (resin, whose 10% modulus is greater than 2.3, but not more than 3.0) of the resin, containing a two-component polyurethane resin and polyurethane resin, which was used to form the colored coating layer, was contained in an amount from 48 to 90 weight percent, in which, in particular, applies 78 weight percent of a two-component aliphatic polyurethane, which is a matting agent (whose 10% modulus is 2.88; see figure 3). This value falls into the aforementioned range.

The soft component (resin, whose 10% modulus is greater than 0.0, but not more than 1.0) of the resin containing a two-component polyurethane resin and polyurethane resin, which was used to form the colored coating layer, was contained in an amount of 52 to 10 weight percent, in which, in particular, applies 22 weight percent of a two-component aliphatic polyurethane (whose 10% modulus is 0.30; see FIG. 6), giving a total content of the soft component of 22 weight% (within the composition range of the coating film of the present invention).

To form the aforementioned topcoat layer, the middle component (resin, whose 10% modulus is greater than 1.0, but not more than 2.3), a resin containing a two-component polyurethane resin and polyurethane resin was not used, while the rigid component was contained in an amount of 27 weight percent (which is comparable with the content of the average component from 15.0 to 35.0 weight percent according to the present invention, which was one of the differences), and a soft component (resin, whose 10% modulus is more than 0.0, but not more than 1, 0) resin containing a two-component polyurethane resin and polyurethane resin, contained a total of 73 weight percent, including 25 weight percent of two-component aliphatic polyurethane (matting resin) (whose 10% module is 0.67; see Fig. 9), 25 weight percent of another two-component aliphatic polyurethane resin ( whose 10% modulus is 0.54; see FIG. 10) and 23 weight percent of an acrylic polymer-urethane polymer copolymer (whose 10% modulus is 0.11; see 11) (within the compositional range of the coating film according to the present invention).

(B) The following two points were evaluated. According to a preliminary measurement of genuine leathers using the KES-SE-SR-U friction roughness measuring instrument (manufactured by Kato Tech), the leathers were considered acceptable when their (a) smoothness (SMD) was 2.5 μm or less, and the evenness (MIU / MMD) was 25 or more, and (b) the result of the endurance test was 4000 cycles or more. Therefore, they came to the conclusion that skin problems, the solution of which is provided by the present invention, are solved when two evaluation criteria (a) and (b) are fulfilled.

(C) In Comparative Example 1 (a), the smoothness (SMD) was 2.60 μm and the evenness (MIU / MMD) was 17.0, while the aforementioned score (b) was 20,000 cycles according to the estimate of paragraph (B). Smoothness (SMD) and evenness (MIU / MMD) values were outside of the evaluation criterion (a).

Example for comparison 2

(A) In comparative example 2, a cover film suitable for furniture, etc., was formed on the same suitable base obtained in example 2. It is known that leathers used for furniture should have soft properties.

It has been shown that if a film is formed using a method not strictly corresponding to the compositions specified in the present invention, the evaluation criteria may not be met.

Foundation preparation

As the basis used natural leather obtained in the above test 6 of example 1.

The formation of a coating film is described below.

A coating film of a primer was formed on natural skin (coating consumption = 40 g / m ² , film thickness = 5 μm), after which a layer of the main coating was formed (coating consumption = 45 g / m ² , film thickness = 9 μm).

On top of the main coating layer, the next colored coating layer and a topcoat layer were formed.

The rigid component (resin, whose 10% modulus is greater than 2.3, but not more than 3.0) of the resin, containing a two-component polyurethane resin and polyurethane resin, which was used to form the colored coating layer, was contained in an amount from 48 to 90 weight percent, in which, in particular, applies 25 weight percent of a two-component aliphatic polyurethane, which is a matting agent (whose 10% module is 2.77; see figure 4), indicating that the content of the hard component is insufficient compared to the composition of the coating film according tothe present invention.

The soft component (resin, whose 10% modulus is greater than 0.0, but not more than 1.0) of the resin containing a two-component polyurethane resin and polyurethane resin, which was used to form the colored coating layer, was contained in an amount of 52 to 10 weight percent, in which, in particular, uses a two-component aliphatic polyurethane (whose 10% module is 0.54; see figure 5) and another two-component aliphatic polyurethane (whose 10% module was 0.79), giving a total content of the soft component of 75 weight% (which is out of range while remaining coating film of the present invention.)

To form the aforementioned topcoat layer, the middle component (resin, whose 10% modulus is greater than 1.0, but not more than 2.3) of a resin containing a two-component polyurethane resin and polyurethane resin was not used, while the soft component (very soft resin , whose properties cannot be measured) was contained in an amount of 100% (which is outside the range of the composition of the coating film of the present invention).

(B) The following two points were evaluated. According to a preliminary measurement of genuine leathers using the KES-SE-SR-U friction roughness measuring instrument (manufactured by Kato Tech), the leathers were considered acceptable when their (a) smoothness (SMD) was 2.5 μm or less, and the evenness (MIU / MMD) was 25 or more, and (b) the result of the endurance test was 4000 cycles or more. Therefore, they came to the conclusion that skin problems, the solution of which is provided by the present invention, are solved when two evaluation criteria (a) and (b) are fulfilled.

(C) In comparison example 2 (a), the smoothness (SMD) was 1.05 μm and the evenness (MIU / MMD) was 42.2, while the aforementioned score (b) was 500 cycles. Although smoothness (SMD) and evenness (MIU / MMD) met the evaluation criteria (a), the evaluation criterion (b) was significantly different.

Example for comparison 3

(A) In comparison example 3, a coating film was formed on the same suitable base obtained in example 2 using a method not strictly following the components and compositions specified in the present invention, where, in particular, a topcoat layer was formed by mixing hard , medium and soft components.

Foundation preparation

As the basis used natural leather obtained in the above test 6 of example 1.

The formation of a coating film

The formation of a coating film is described below.

A coating film of a primer was formed on natural skin (coating consumption = 40 g / m ² , film thickness = 5 μm), after which a layer of the main coating was formed (coating consumption = 45 g / m ² , film thickness = 9 μm).

On top of the main coating layer, the next colored coating layer and a topcoat layer were formed.

The rigid component (resin, whose 10% modulus is greater than 2.3, but not more than 3.0) of the resin, containing a two-component polyurethane resin and polyurethane resin, which was used to form the colored coating layer, was contained in an amount from 48 to 90 weight percent, in which, in particular, used 78 weight percent of a two-component aliphatic polyurethane, which is a matting agent (whose 10% module is 2.88; see figure 3), which is within the range specified in the present invention.

The soft component (resin, whose 10% modulus is greater than 0.0, but not more than 1.0) of the resin containing a two-component polyurethane resin and polyurethane resin, which was used to form the colored coating layer, was contained in an amount of 52 to 10 weight percent, in which, in particular, used 22 weight percent of a two-component aliphatic polyurethane (whose 10% modulus is 0.30; see Fig.6), which is within the range specified in the present invention.

The middle component (resin, whose 10% modulus is greater than 1.0, but not more than 2.3) of the resin containing a two-component polyurethane resin and polyurethane resin, which was used to form the topcoat layer, was contained in an amount of 15.0 to 35.0 weight percent, in which, in particular, 33 weight percent of a two-component aliphatic polyurethane resin (whose 10% modulus is 1.92) was used (which is outside the composition range of the coating film of the present invention). In addition, the hard component was used in an amount of up to 22 weight percent, although such a percentage is not indicated in the present invention (which is outside the composition range of the coating film of the present invention.)

The soft component of the aforementioned top layer consisted of 45 weight percent of an acrylic polymer-urethane polymer copolymer (whose 10% modulus is 0.11; see FIG. 11) (which is outside the composition range of the coating film of the present invention).

(B) The following two points were evaluated. According to a preliminary measurement of genuine leathers using the KES-SE-SR-U friction roughness measuring instrument (manufactured by Kato Tech), the leathers were considered acceptable when their (a) smoothness (SMD) was 2.5 μm or less, and evenness (MIU / MMD) was 25 or more; and (b) the result of the wear test was 4000 cycles or more. Therefore, they came to the conclusion that skin problems, the solution of which is provided by the present invention, are solved when two evaluation criteria (a) and (b) are fulfilled.

(C) In comparison example 3 (a), the smoothness (SMD) was 1.25 μm and the evenness (MIU / MMD) was 16.5, while the aforementioned estimate (b) was 10,000 cycles according to the estimate of paragraph (B). In any case, the evenness value (MIU / MMD) is outside of the evaluation criterion (a).

Example for comparison 4

(A) In comparison example 4, a cover film was formed suitable for furniture, etc., on a suitable basis similar to that in comparison example 2. It is known that leathers used for furniture should have soft characteristics.

It has been shown that if a film is formed using a method not strictly corresponding to the compositions specified in the present invention, the evaluation criteria may not be met.

Foundation preparation

As the basis used natural leather obtained in the above test 6 of example 1.

The formation of a coating film

A coating film of a primer was formed on natural skin (coating consumption = 40 g / m ² , film thickness = 5 μm), after which a layer of the main coating was formed (coating consumption = 45 g / m ² , film thickness = 9 μm).

On top of the main coating layer, the next colored coating layer and a topcoat layer were formed.

The rigid component (resin, whose 10% modulus is greater than 2.3, but not more than 3.0) of the resin, containing a two-component polyurethane resin and polyurethane resin, which was used to form the colored coating layer, was contained in an amount from 48 to 90 weight percent, in which, in particular, used 78 weight percent of a two-component aliphatic polyurethane, which is a matting agent (whose 10% module is 2.88; see figure 3).

The soft component (resin, whose 10% modulus is greater than 0.0, but not more than 1.0) of the resin containing a two-component polyurethane resin and polyurethane resin, which was used to form the colored coating layer, was contained in an amount of 52 to 10 weight percent, in which, in particular, 22 weight percent of only two-component aliphatic polyurethane (whose 10% modulus is 0.30; see FIG. 6) (which is within the composition range of the coating film of the present invention) was used.

To form the aforementioned topcoat layer, the middle component (resin, whose 10% modulus is greater than 1.0, but not more than 2.3), a resin containing a two-component polyurethane resin and polyurethane resin was not used, while the soft component consisted of 33 weight percent of an acrylic polymer-urethane polymer copolymer (whose 10% modulus is 0.11; see FIG. 11) and 67 weight percent of a very soft resin whose properties cannot be measured (which is outside the composition range of the coating film of the present invention).

(B) The following two points were evaluated. According to a preliminary measurement of genuine leathers using the KES-SE-SR-U friction roughness measuring instrument (manufactured by Kato Tech), the leathers were considered acceptable when their (a) smoothness (SMD) was 2.5 μm or less, and evenness (MIU / MMD) was 25 or more; and (b) the result of the wear test was 4000 cycles or more. Therefore, they came to the conclusion that skin problems, the solution of which is provided by the present invention, are solved when two evaluation criteria (a) and (b) are fulfilled.

(C) In Comparative Example 4 (a), the smoothness (SMD) was 0.87 μm and the evenness (MIU / MMD) was 30.0, while the aforementioned score (b) was 2000 cycles. Although smoothness (SMD) and evenness (MIU / MMD) meet the evaluation criterion (a), the evaluation criterion (b) was significantly different.

Example for comparison 5

Used the same basis described above in example for comparison 1.

(A) In comparison example 5, skin obtained by grinding the skin, in turn obtained by the usual tanning process using glutaraldehyde, as in example 11, was used, and a coating film was formed corresponding to the components and content indicated in the present invention to such a basis in which case positive results could not be achieved.

Foundation preparation

The prepared base was the skin obtained by grinding the skin, in turn, obtained by the usual method of tanning using glutaraldehyde, as in example 11.

The formation of a coating film

A primer coating film was formed on natural skin (coating consumption = 40 g / m ² , film thickness = 5 μm), after which a layer of the main coating was formed (coating consumption = 45 g / m ² , film thickness = 9 μm).

On top of the main coating layer, the next colored coating layer and a topcoat layer were formed.

The rigid component (resin, whose 10% modulus is greater than 2.3, but not more than 3.0) of the resin, containing a two-component polyurethane resin and polyurethane resin, which was used to form the colored coating layer, was contained in an amount from 48 to 90 weight percent, in which, in particular, used 25 weight percent of a two-component aliphatic polyurethane, which is a matting agent (whose 10% module is 2.88; see figure 3) and 53 weight percent of another two-component aliphatic polyurethane (whose 10% module is 2.77 ; see figure 4), I give total amount of 78 weight%.

The soft component (resin, whose 10% modulus is greater than 0.0, but not more than 1.0) of the resin containing a two-component polyurethane resin and polyurethane resin, which was used to form the colored coating layer, was contained in an amount of 52 to 10 weight percent, in which, in particular, the soft component contained 22 weight percent of a two-component aliphatic polyurethane (whose 10% module is 0.30; see FIG. 6), and the hard component contained 78 weight percent of a two-component aliphatic polyurethane, which is a matting agent (whose 10% modulus is 2.88; see FIG. 3). The content of the hard component and the soft component of the painted coating layer was within the ranges indicated in the present invention.

The middle component (resin, whose 10% modulus is greater than 1.0, but not more than 2.3) of the resin containing a two-component polyurethane resin and polyurethane resin, which was used to form the aforementioned topcoat layer, was contained in an amount of from 15.0 to 35, 0 weight percent, in which, in particular, 25 weight percent of a two-component aliphatic polyurethane resin (whose 10% modulus is 1.89; see FIG. 8), which was within the range of the present invention, was used.

The soft component (resin, whose 10% modulus is greater than 0.0, but not more than 1.0) of a resin containing a two-component polyurethane resin and a polyurethane resin, which was used to form the aforementioned topcoat layer, was contained in an amount of from 85.0 to 65, 0 weight percent, in which, in particular, 25 weight percent of a two-component aliphatic polyurethane (matting resin) (whose 10% modulus is 0.67; see Fig. 9), 25 weight percent of another two-component aliphatic polyurethane resin (whose 10% the module is 0.54; see figure 10) and 25 ve ovyh percent copolymer of acrylic polymer-urethane resin (whose 10% modulus is 0.11;. 11 cm), giving a total content by weight of 75%. It was also within the range indicated in the present invention.

(B) The following two points were evaluated. According to a preliminary measurement of genuine leathers using the KES-SE-SR-U friction roughness measuring instrument (manufactured by Kato Tech), the leathers were considered acceptable when their (a) smoothness (SMD) was 2.5 μm or less, and evenness (MIU / MMD) was 25 or more; and (b) the result of the wear test was 4000 cycles or more. Therefore, they came to the conclusion that skin problems, the solution of which is provided by the present invention, are solved when two evaluation criteria (a) and (b) are fulfilled.

(C) Regarding the skin evaluation results of Comparative Example 5, the smoothness (SMD) was 2.06 μm, the evenness (MIU / MMD) was 19.5, and the abrasion test with an abrasion resistance evaluation tool gave 10,000 cycles (Gakushin). Evenness (MIU / MMD) did not meet the criteria.

(D) The results obtained in the examples for comparison 1 and 5 were compared. In the comparison example 5, the smoothness (SMD) was 2.06 μm and the evenness (MIU / MMD) was 19.5. On the other hand, in Comparative Example 1, the smoothness (SMD) was 2.60 μm, and the evenness (MIU / MMD) was 17.0.

These results confirm that when skin obtained using a conventional tanning process using glutaraldehyde is used as the base, the conditions of comparative example 5, corresponding in terms of the components and content of the coating film specified in the present invention, could provide more positive results in comparison with the conditions of Comparative Example 1, wherein the coating film was different from the coating film of the present invention in terms of both smoothness (SMD) and evenness (MIU / MMD). This, obviously, is the basis on which the expert opinion is formed that by forming a coating film of the present invention on commonly known skin, positive results can be achieved in terms of smoothness (SMD) and evenness (MIU / MMD).

Industrial application

Genuine leather according to the present invention obtained by forming a primer, a base coat and then a colored coating layer and a top coating layer formed by certain resins on the surface of natural leather obtained by the tanning step of a leather using a tanning agent containing chromium or glutaraldehyde, as well as the steps retanning, dyeing and fatliquoring, demonstrates the distinctive characteristics of the skin, such as evenness and smoothness, inherent only in natural skin, and therefore can effect implicitly applied in various fields, in addition to parts of the car interior.

Claims (5)

1. Genuine leather, characterized in that it is produced by producing genuine leather using a tanning step of a skin using a tanning agent containing chrome or glutaraldehyde, as well as stages of retanning, dyeing and fatliquoring, and then forming a primer on the surface of genuine leather in the indicated order, the main coatings, a layer of a colored coating formed by mixing 48-90 wt.% hard component (resin, whose 10% modulus is more than 2.3, but not more than 3.0) of a resin containing at least a two-component polyurethane resin 52-10 wt.% Soft component (resin, whose 10% modulus is greater than 0.0, but not more than 1.0) of a resin containing at least a two-component polyurethane resin, and a topcoat layer formed by mixing 15-35 wt.% of the middle component (resin, whose 10% modulus is greater than 1.0, but not more than 2.3) of a resin containing at least a two-component polyurethane resin, with 65-85 wt.% soft component (resin, whose 10 % module is greater than 0.0, but not more than 1.0) of a resin containing at least a two-component polyurethane resin. 2. Genuine leather according to claim 1, characterized in that said tanning agent contains glutaraldehyde and natural skin obtained by a tanning step of a leather using said tanning agent containing glutaraldehyde, as well as stages of retanning, dyeing and fatliquoring, are obtained by:
(1) pretreatment steps before tanning leather;
(2) a tanning step using glutaraldehyde as a tanning agent;
(3) the stage at which the skin is tanning using a tanning agent consisting of a synthetic tanning agent and resin, where the synthetic tanning agent consists of: (A) a condensation product of aromatic sulfonic acid and formaldehyde, or aromatic sulfonic acid and a condensation product of aromatic sulfonic acid and formaldehyde; (B) a methylene-containing cyclocondensation product of aromatic sulfonic acid and a hydroxyaromatic compound; or an aromatic sulfonic acid and a methylene-containing cyclocondensation product of aromatic sulfonic acid and a hydroxyaromatic compound; and (C) glyoxal, while the resin consists of: (A) a polymer or mixture of acrylic acid, methacrylic acid, an ester of acrylic acid or an ester of methacrylic acid or a copolymer of any combination of the foregoing, or a mixture of such copolymers, and (B) the polycondensation product of melamine and formaldehyde, where the skin is tanning using a tanning agent of the aforementioned composition, after which it is dyed and then subjected to fatliquoring using a lubricating agent consisting of: (A) synthetic oil and natural la or (B) mixed oil containing synthetic oil and natural component; and
(4) post-retreatment post-processing steps. 3. Genuine leather according to claim 1, characterized in that said tanning agent contains glutaraldehyde and natural skin obtained by a tanning step of a skin using said tanning agent containing glutaraldehyde, as well as stages of retanning, dyeing and fatliquoring, are obtained using:
(1) pretreatment steps before tanning leather;
(2) a tanning step using glutaraldehyde as a tanning agent;
(3) the stage at which the skin is tanning using a tanning agent consisting of a synthetic tanning agent, a resin and an aluminum compound, the synthetic tanning agent consisting of: (A) a condensation product of aromatic sulfonic acid and formaldehyde or aromatic sulfonic acid and an aromatic sulfonic acid condensation product and formaldehyde; (B) a methylene-containing cyclocondensation product of aromatic sulfonic acid and a hydroxyaromatic compound; or an aromatic sulfonic acid and a methylene-containing cyclocondensation product of aromatic sulfonic acid and a hydroxyaromatic compound; and (C) glyoxal, while the resin consists of: (A) a polymer or mixture of acrylic acid, methacrylic acid, an ester of acrylic acid or an ester of methacrylic acid, or a copolymer of any combination of the foregoing, or a mixture of such copolymers; and (B) a polycondensation product of melamine and formaldehyde, wherein the skin is tanning using a tanning agent of the aforementioned composition, after which it is dyed and then fattened using a lubricating agent consisting of: (A) synthetic oil and natural oil or (B) mixed oil containing synthetic oil and a natural component; and
(4) post-retreatment post-processing steps. 4. Genuine leather according to claim 1, characterized in that when its surface is measured using a KES-SE-SR-U friction roughness measurement tool, smoothness (SMD) is 2.5 μm or less, evenness (MIU / MMD) is 25 or more, and the result of a wear test using a Gakushin abrasion resistance assessment tool is 4000 cycles or more. 5. Genuine leather according to claim 1, characterized in that genuine leather is used as a material for an automobile interior.

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